Tips for Growing and Selecting

Transcription

1 Deciduous Fruit Trees in Southern California a Tips for Growing and Selecting

2 The Right Plant In The Right MICROCLIMATE Place Geographic Location Elevation Topography Exposure

3 Microclimate and Sun / Heat Fruit trees generally require at least 8 or more hours of full, direct sun per day. Deciduous fruit trees can be grown in locations which receive less than optimum sun exposure during the winter months. Many fruit develop sugar and sweetness in response to sun and heat. Some fruit and nut Some fruit and nut varieties require high heat to properly mature the fruit.

4 Cold air flows like water and settles in low areas. Cold pockets develop in low areas and behind buildings and obstacles on slopes when airflow is blocked. Frost sensitive fruit trees should be placed in protected areas or in areas where cold air drains away. Many deciduous fruit trees have chilling requirements that must be met in order for proper growth and fruit production to occur. Cold and Chill / Frost

5 Chill Hours Chill hours are the number of hours of cold that are required to break down or degrade the growth inhibiting hormones that cause a deciduous fruit tree to enter dormancy and that keep a plant dormant, so that normal growth can resume. They are most commonly defined as the number of hours that occur during the dormant season of the plant which fall between the temperatures of 45 degrees and 32 degrees ees Fahrenheit. e If day temperatures following a night of chill raise above degrees, then the hours above those temperatures are subtracted from the accumulated chill hours. Deciduous fruit trees often have chilling requirements of 600 or 1000 hours or more that are needed for proper growth and fruit production. This definition iti of chill hours is not always accurate, but this is the most commonly accepted definition. The average # of chill hours varies depending on the year and microclimate. In San Diego the average # chill hours are: Coastal strip (within miles of coast) = chill hours Median areas (between 10 & 25 miles of coast La Mesa, Clairemont, etc.) = chill hours Inland areas (El Cajon, Spring Valley, Escondido, Jamul, etc.) = chill hours

6 Tree Selection - Chill Hours The variety of the type of fruit is EVERYTHING! Most fruit types have varieties that require relatively few hours of chill ( hours = low chill varieties). If a plant does not receive the required number of chill hours to grow properly, the growth or performance of the plant will be impaired. The difference between the number of chill hours required and the number of chill hours received will determine the severity of the effect. If the difference is relatively minor, normal vegetative growth may occur, however flowering and fruiting will be impaired. If the difference is greater, vegetative growth will be sluggish and will develop at a less vigorous rate than normal. Flowering and fruiting may be slight or non-existent. If the difference is relatively large, the tree will remain dormant much later than normal. Growth will be sluggish and flowering will not occur. The tree will enter dormancy earlier in the fall than normal. If chill hour requirements are not met for several consecutive years, death of the tree will probably occur.

7 Chill Hours Having a low chill fruit tree in an area that receives a high number of chill hours may also cause problems. In this case, the tree may receive the necessary number of chill hours to overcome dormancy very early in the season. If a period of warm weather occurs, the tree may break dormancy and begin growing. Subsequent freezing temperatures will often kill this new growth. The tree may survive and re-grow when warm weather returns, however flowering will often not occur during the new growth flush. If this pattern occurs more than once during the winter season, the tree may be killed. Selecting fruit tree varieties with chilling requirements appropriate to your microclimate is an important consideration for successful fruit tree growing. (Visit the CRFG website at

8 Tree Size The mature size of a fruit tree is usually divided into 3 primary classifications. Dwarf, Semi-Dwarf, and Standard. Size will vary from species to species and to a lesser degree variety to variety. Most fruit trees are grafted onto rootstocks, and many times, rootstocks will influence the mature size of the tree. Correct pruning can reduce the mature tree size by roughly 25% or more.

9 Soil Percolation or Drainage Percolation or drainage is the movement of water vertically into the soil. A slope does not ensure good drainage. Soil texture frequently affects the percolation rate. Sand Good aeration and drainage. Does not compact easily. Poor water retention. Nutrient poor, does not hold nutrients well. Clay Good water retention. Nutrient rich and retains nutrients well. Poor aeration and drainage. Compacts easily. Silt / Loam Best situation. Good water retention, aeration, drainage, nutrient availability and retention. Does not compact easily.

10 Soil Percolation and Drainage In order for tree roots to grow and survive, they must have a soil environment that has the right balance of water and air. Too much or not enough of either will result in root death. To perform a percolation test, dig a hole two to three feet deep and fill it with water twice. The water in the hole should drain completely away within 12 hours to be considered to have adequate drainage for most trees. If above average drainage is preferred (as for avocados, papaya, etc.), the water should drain within 8 hours. Soil amendments DO NOT correct soils with poor drainage! Organic amendments only affect the soil environment in the area of the soil that they are mixed. To be beneficial to plant growth, amendments must be mixed into a large enough area to support a substantial portion of the root system of the mature plant or plants. Organic amendments are only recommended or useful when preparing an area for planting annuals and small perennials.

11 Organic Amendments Mixing organic amendments into planting holes for trees and shrubs is generally not recommended or beneficial. At best, these amendments do no good as the root system on healthy plants will develop well beyond the amended planting hole. At worst, amendments in a planting hole can: Restrict or inhibit the development of roots into the non-amended native soil. Restrict the movement of water into the non-amended soil, forming a perched water table and causing the soil in the planting hole to become saturated and soggy. Will decompose over time, causing the amended soil to compact and the crown of the plant to settle below surface of the non-amended soil. This settling frequently causes crown rot and can kill the plant.

12 Soil Percolation and Drainage Methods of dealing with soils that have inadequate drainage include: 1. Plant in raised beds or on mounds. 2. Install a French drain or a chimney drain. 3. Combine a French drain or a chimney drain with a mound or raised bed. 4. Plant in containers. 5. Find another planting site.

13 Container Soils Potting or container soils are mixtures of organic and inorganic components designed to provide optimum water, air and nutrients for plant root growth. Primarily organic soils, container soils are subject to the same processes of decomposition and compaction as inground soils. Container soils high in wood and bark products decompose more quickly than those with a higher mineral content. Container soils should be considered as temporary and need to be refreshed as they decompose and compact. Always add fresh soil to the bottom of a root ball and never bury the crown of a plant by adding more soil to the top of a potted plant unless the roots of the plant are exposed.

14 Container Soils Commercially available cactus soils are low in organic materials. They decompose less and they decompose more slowly than soils with a high wood and bark content. An excellent long lasting container soil can be created by mixing ing cactus soil with a potting soil that has rice hulls (which decompose much more slowly than wood and bark products) and organic nutrients, such as Kellogg s Patio Plus.

15 Soil ph and Salts When planting into the soil, soil ph and accumulated salts frequently affect the health and performance of fruit trees. Sensitivity to soil ph and accumulated salts will vary by fruit type. Avocado and litchi are most easily damaged by salt. Frequently, the soils in Southern California and the irrigation water we use are both high in ph and in salt. Many fertilizers are also salts and many manures contain high amounts of salt. Both can affect the ph and salt level of the soil.

16 Soil ph Soil ph is the acidity or alkalinity of a soil on a scale of 0-14 with a neutral ph being 7.0, an acid ph being less than 7.0, and an alkaline ph being greater than 7.0. When the soil ph is relatively neutral, all existing plant nutrients are available to root systems. Very acidic and very alkaline soils tend to tie-up plant nutrients which result in nutrient deficiency symptoms in plants. Soil ph also directly affects the soil ecosystem and both the type and the amount of life found in the soil. The optimum ph range of soil varies from plant to plant but a ph range of is generally considered desirable for most plants and soil life.

17 Lowering the ph of Alkaline Soils Sulfur - When sulfur is added to a soil, it combines with water and forms sulfuric acid. This easily breaks down and provides H+ to the soil which, over time, lowers the ph. Other products which help to make a soil more acidic: Oak leaves Bark Coffee grounds Pine needles Humus Canadian Peat Moss Cotton Seed Meal Compost Ammonium-type fertilizers Aluminum Sulfate Lowering the ph of alkaline soils takes time and Lowering the ph of alkaline soils takes time and often relies on the biological activity of organisms living in the soil!

18 Salt problems related to plant growth Most alkaline soils have problems with excessive salt accumulation due to low rainfall in the area as the salts are not leached from the soil. Problems related to high accumulated salts include: Reduced seedling germination and survival. Faster wilting of plants. It is harder for plant roots to take up water in soils high in salts and in fact they may even lose water in very salty soils. Soils with excessive e sodium can break down soil aggregates and result in a dispersed, sealed-off soil surface reducing the percolation rate of the soil. Salt toxicity to leaves causing dead margins. Salty water applied by sprinklers burning foliage. Inability of plant to obtain essential nutrients such as phosphorus and iron.

19 Reclaiming Salty Soils Mulches on the surface slow upward evaporation which can aid in reducing the surface salts. As organic mulches decompose, they form humic acid which helps to lower the soil ph, therefore making salts more soluble. Leaching Soil is flooded with water and the salts are leached through the root zone. This is only practical if water low in salt is available & the soil drainage is moderate to fast. Unfortunately, most saline soils are clay-like and have poor drainage. For leaching, 12 of water is needed to remove about 70-80% of the salt in the top 12 of soil. Gypsum CaSO 4 gypsum will slowly replace the sodium in soil and over time will improve soil structure - the calcium cations bond together soil particles into larger aggregates thus improving soil drainage. the sodium sulfate is now more easily leached from the soil. Gypsum works like this: CaSO 4 + H 2 O + 2Na + = Ca ++ + Na 2 SO 4 + H 2 O

20 Liquid "Gypsum" and Liquid Thrive Liquid "Gypsum" and Liquid Thrive contains a high level of soluble calcium which displaces the sodium. This then creates pore spaces in the soil. The effectiveness of the calcium is compounded by the use of a polyacrylamide (PAM) that attaches to the soil particle and remains in the soil for years, helping the soil structure to resist collapsing. The effect of the PAM is cumulative and long lasting. Benefits: Improves clay soils by displacing sodium immediately. Releases salts, lowering soil EC Improves soil drainage Reduces crusting and improves infiltration of water and nutrients 32 oz. = 200 lbs. dry gypsum

21 Proper Planting Planting hole should 2-3times as wide and only as deep as the trees root ball. Prune any damaged roots, cut any circling roots and score sides of the existing root ball. Backfill with native soil. Starter fertilizers, gypsum, or mycorrhiza can be added at this time. Thoroughly water. Apply 2-3 of organic mulch to the soil surface, well away from the tree trunk. A word about mycorrhiza.

22 Mycorrhiza Mycorrhiza have formed associations with plant roots for over 400 million years. Present in most undisturbed soils, mycorrhiza may be missing from areas where the top layers of soil have been removed, where soils have been compacted, where fungicides or excess fertilizers have been applied or in container (soilless) soil mixes. Mycorrhiza must come into direct contact with a plant s root to form a symbiotic association with the plant! Benefits of Mycorrhiza: Enhanced plant efficiency in absorbing water and nutrients (especially phosphorous) from the soil. Reduces fertility and irrigation requirements. Enhances plant health, vigor and drought resistance and minimizes stress. Increased pathogen resistance/protection. Enhances seedling growth, rooting of cuttings, and plant transplant establishment.

23 Organic Mulches Organic material which h falls or is applied to the surface of the soil and decomposes is all considered organic mulch. There, organisms feed on them and mix the organic material with the upper soil layers; these organic compounds become part of the soil formation process, ultimately shaping the type of soil formed. Mulches gradually incorporate into the soil profile from the top down. Applying organic mulches to the entire surface of a soil can affect the soil in the entire growing environment. Mulch will decompose and needs to be reapplied at least annually. Mulches can also help to moderate the soil environment by affecting soil surface temperature and moisture level.

24 Mulches Mulching a large portion of the feeder root zone is one of the most beneficial things you can do for your trees. Mulch should be at least 2 to 3 inches deep and should not touch the trunk of the tree or plant. It should extend beyond the drip line. Particle size, texture and degree of decomposition all affect the physical and chemical properties of organic mulches. Coarse materials tend to Last longer Reduce soil compaction Suppress weeds Fine materials tend to Decompose more quickly Have better moisture holding ability as well as provide more nutrients to the soil as the decompose Hold onto nutrients reducing the effects of leaching Act as binding agents

25 Proper Staking Stake(s) should be placed away from the trunk and the tree tied loosely in two or three opposing directions if necessary. Stakes should only be as tall as necessary to keep the plant upright. Tree tie material should be at least 1 inch wide wherever it contacts the bark. Stakes should be removed as soon as possible. Spread or train branches to develop pproper p tree shape and to develop strong branch structure.

26 Proper Planting and Staking Only light pruning is recommended at planting and for the first year! Remove dead or damaged branches, co-dominant branches and branches with narrow crotch angles. Leave temporary branches that will be removed later as the tree grows. Do Not top the tree! Hormones Scaffold branches should occur with which stimulate root development vertical and radial spacing to develop are produced in the apical tips of strong branch structure. branches. Topping results in poor branch development and tree structure. Spread or train branches to develop proper tree shape and to develop strong branch structure.

27 Training Training branches to grow in specific directions is often a viable option to pruning. This can take advantage of growth which h has already developed d instead of pruning off already grown branches and waiting for new branches to grow. Using training techniques can avoid the wounds made by pruning and therefore reduce the problems associated with those wounds. Training should be done when branches are young and flexible enough to bend into shape without breaking or splitting the branch or trunk. Weights, guy wires, stakes or spreaders can be used to train branches. If ties are used, the tie material should be at least 1" wide wherever it comes into contact with the bark of the tree to prevent damage to the bark.

28 Watering fruit The trees age and size as well as the soil climate The trees age and size as well as the soil, climate, season and other factors affect watering. There are three key principles to proper watering.

29 KEY TO PROPER WATERING #1 Water the proper area the Feeder Root Zone! Water near the trunk or stem on newly planted plants so that you wet the original root ball. Water at the dripline and beyond on plants which are established in the ground. (The plant may take from a few weeks to a one year or more to become established depending on the type and size of the plant, the time of year that it was planted, soil conditions, cultural practices and other variables.) Water further away from the trunk or stem as time progresses and as the plant grows larger in diameter.

30 How Plant Roots Grow Trees growing in urban areas seldom develop taproots. t Root systems actually consist of larger perennial roots and smaller, short-lived, feeder roots. Large, woody tree roots and their primary branches increase in size and grow horizontally. These roots are usually located in the top 6 to 36 inches of soil. The small feeder roots constitute the major portion of the root system's surface area. Feeder roots are located throughout the entire area under the canopy of a tree. As much as 50 percent of the root system grows beyond the drip line and may extend as far as two to three times the height of the tree. A Trees feeder roots grow out from large woody roots and usually grow up toward the soil surface. At the surface, feeder roots mix with lawn and shrub roots and compete for the water, oxygen and minerals that are more abundant near the surface. Roots on trees have 3 main functions: 1. Anchorage 2. Food Storage 3. Absorption of water and nutrients = Feeder Roots

31 Depth of Water Extraction by Roots Most water is taken up by roots from the top 12 of soil (40% - 70% or more). Up to 90% of the roots that take up water and nutrients are located in the top 36 of soil. Watering methods can determine root depth: Light, shallow watering encourages shallow roots. This results in plants that dry out easily and can blow over in storms. Deep, infrequent watering is best to encourage roots to penetrate deeply in the soil. 1 of water penetrates the ground 1 in sandy soil. It takes 2-3 of water to penetrate the ground 1 in clay soil.

32 KEY TO PROPER WATERING #2 Water with sufficient amount of water enough to thoroughly wet the entire depth of the Feeder Root Zone. 1 of water penetrates the ground 1 in sandy soil, it takes 2 of water to penetrate the ground in clay soil. 90% of feeder roots are found in the top 3 of soil! (70% are in the top 1 of soil.) Water to an average depth of 1 to 3 at each watering for plants that have been established in the ground. Smaller plants generally have shallower root systems than larger plants. As a general rule, water to a depth of 6 to 1 foot for plants 1 or less in height, to a depth of 2 foot for plants 1 to 4-5 feet in height and to a depth of 3 for plants larger than 5 feet in height. For plants in containers, water with enough water to leach excess salts out of the container and to thoroughly wet the entire root ball at each watering.

33 KEY TO PROPER WATERING #3 Water at the correct interval often enough to keep the plant from wilting, but infrequently enough to allow air to penetrate the soil. Roots can drown if the soil is kept constantly wet! Watering frequency will vary with the time of year, location, size of the plants, soil, weather conditions and many other variables. On average: Water new plants in the ground 1-2 times per week. Water older established plants in the ground 1 time per week to 1 time per month depending on the variables. Water plants in containers 1-3 times per week. There are very few exceptions where plants should be watered every day! Watering too frequently will exclude oxygen from the soil and cause roots to drown as well as promote diseases!

34 Fertilizers There are 17 elements that plants need in order to successfully grow and complete their life cycle. These elements are called the Essential Elements. 14 of the elements are minerals taken in by roots from the soil. These essential elements are broken down into two categories: macro elements and micro elements. Macro elements are also know as major elements. The macro elements that are minerals taken in by roots from the soil are nitrogen, phosphorus, potassium, calcium*, magnesium*, and sulfur* These elements are needed in larger quantities by the plant than the micro elements. (* elements are sometimes referred to as secondary elements.) Micro elements are also know as trace or minor elements. The micro elements are Boron, Zinc, Manganese, Chlorine, Iron, Molybdenum, and Copper and Nickel. These elements are needed by the plant in smaller amounts than the macro elements. The availability of these nutrients for plants to absorb from the soil are affected by the soil ph and the microorganisms which live in the soil.

35 Fertilizer Types Liquids: Generally fast acting but quickly lost from the soil due to leaching. Must be applied more frequently than other forms of fertilizer. Easily applied to a large portion of the feeder root zone. Useful as a foliar fertilizer, commonly used to correct micronutrient deficiencies. Stakes or spikes and tablets: Concentrate the fertilizer in small areas. Only the roots near these locations have nutrients available, resulting in a very small portion of the feeder roots utilizing the fertilizer application. Must be placed in the feeder root zone and must be placed in many locations to maximize benefit. Most useful when used in containers. Granules, meals, and manures: Easily applied to a large portion of the feeder root zone. Frequently longer lasting but slower acting than liquid fertilizers. May be subject to being washed away if applied to slopes. User may have a greater risk of over applying and burning their plants. Apply fertilizer evenly on mulched and unmulched surfaces out to about 1½ times the crown radius.

36 Fertilizers Fast-release or water-soluble fertilizers are less expensive than slow-release products, which release nitrogen over an extended period; however, the nutrients in a fast-release fertilizer may leach quickly through the soil. Slow- or controlled-release fertilizers have extended release periods compared to fast-release fertilizers whose nitrogen is water-soluble and readily available to the plants. Organic fertilizers Most rely on soil organisms to convert them to nutrients which are available for absorption by plant roots. Often temperature dependant and slow release. Many provide food for soil organisms and help to improve the soil structure and the soil ecosystem. Conventional ie. Synthetic fertilizers More formulations and types available. Not temperature dependant. Provide nutrients but does not improve soil health.

37 The Effect of Micro-organisms on Nutrient Absorption by Plants Soil micro-organisms can directly affect nutrient absorption by plants. The nutrients that are most affected include Nitrogen and Phosphorous. Sulfur (S) is usually found in low levels in soils and it is frequently obtained by decomposing organic matter. The application of mulches, soil amendments or fertilizers that are high in salts, release high levels of nutrients too quickly, modify soil ph outside a desirable ph range, or cause soils to become too soggy, excluding adequate aeration, can kill soil micro-organisms! Organic fertilizers and manures frequently provide food to the organisms which live in the soil as well as provide necessary plant nutrients. Byproducts of decomposition of these organic fertilizers and manures may also be beneficial (such as humic acid).

38 Nitrogen - the nitrogen cycle. Nitrogen is both added to the soil environment and lost from the soil environment by natural processes. This is known as the Nitrogen Cycle. Nitrification cato Nitrogen Fixation is the change of atmospheric nitrogen (N 2 gas) into NH 4 + by bacteria and some algae. This NH 4 + is now or will soon be available to plant roots. The decomposition of organic matter releases NH4+ into the soil for absorption by plant roots. The amount of NH4+ depends on the origin of the organic matter.

39 The Nitrogen Cycle - N Loss Denitrification ifi ti Nitrate (NO 3 -) can be changed to N 2 gas by certain bacteria in the soil. This occurs when soils are saturated and the bacteria are in need of oxygen. The bacteria take the oxygen from the nitrate and release it as N 2 gas. This gas bubbles to the surface and the nitrogen is lost. Tends to be worse in soils high in manures and in soils with poor drainage. - Immobilization Bacteria, fungi, and algae take up ammonium and nitrates from the soil for their own growth and therefore make it unavailable for plants. This tends to occur when large amounts of organic matter are introduced to the soil and is worse when the organic matter has a high C/N ratio. All of the nitrogen will be released to the soil upon the death of the microorganisms.

40 Nitrogen (N) The most critical element in plant growth. This is the nutrient that is most commonly lacking in soils and most frequently needs to be added to soils. Can be absorbed into roots in only two forms: NH 4 + (ammonium) & NO 3 - (nitrate). The nitrate form of nitrogen is very prone to leaching. Sands and well drained soils tend to lose NO3- very easily during high rainfall or frequent irrigation. Fertilizing with the ammonium form of nitrogen (NH4+) is less prone to leaching as the + charge tends to bond with the negatively charged clay particles. Ammonium Volatilization occurs when ammonium fertilizers are applied to the surface of alkaline soils. These soils, typically high in calcium and carbonate, can react with the ammonium fertilizer and result in losses of up to 30% to the atmosphere. Ammonium fertilizers should be incorporated into the soil to lessen this loss or covered with mulches when applied to the soil surface. The addition of some form of nitrogen type fertilizer (organic or inorganic) is most often needed to maintain plant health on most types of plants!

41 Nitrogen Deficiency Symptoms Light green to yellow color on leaves. Older leaves show symptoms first Leaves may go completely yellow but still be alive. Yellowing occurs from the tip of the leaf downward and may later dry up. Plants are spindly and stunted

42 Phosphorus (P) The second most needed d plant nutrient. t It is the least mobile in soil and minimally affected by the leaching processes. Most plants get phosphorus by organic matter breakdown near the roots. Even though phosphorus may be present in the soil, it can be easily tied up by iron, aluminum, and calcium depending on the ph of the soil. Mycorrhiza which have formed associations with plant roots can greatly increase the ability of the plant to absorb phosphorous. Addition of phosphorus fertilizer is often necessary due to the high need of plants and the ease of phosphorus tie-up. It is best when it is worked lightly into the soil or when covered by an organic mulch.

43 The Phosphorous Cycle

44 Phosphorus Deficiency Symptoms Leaves can show a dark green or purple color. Yellowing of the leaves later occurs and leaf drop follows Flowering is poor or non-existent.

45 Soil Nutrients The Physical or Chemical Properties of Soil can also affect the availability of certain soil nutrients. These include: Potassium (K) is usually very present tin soils in the mineral lform of feldspar but is very insoluble resulting in a very small amount available to plants. Therefore, fertilizers are often needed. Calcium (Ca) is very seldom deficient, except in very sandy soils. Calcium is very soluble and wet, rapidly draining soils may leach out calcium. Iron (Fe) is generally found in most soils but can be tied up on alkaline soils. Manganese (Mn) is usually readily available to plants except in highly alkaline soils. Can be a toxic element in highly acidic soils. Zinc (Zn) is tied up in highly alkaline soils and can also be leached in sandy soils.

46 Potassium (K) Usually very present in soils in the mineral form of feldspar (KAlSi 3 O 8 )b but tis very insoluble resulting in a very small amount available to plants. Therefore, fertilizers are sometimes needed. Uses in the plant: helps iron move throughout the plant aids in fighting plant diseases strengthens cell walls aids in frost protection Deficiency Symptoms Yellowing occurs mainly on the margin of the leaves and does not extent inward until severe symptoms show Leaf edges turn brown and leaf edges dry up and curl under

47 Magnesium Rarely deficient in plants. Often naturally found in soils in the mineral dolomitic limestone CaMg(CO 2 ) 2. Aids in the uptake of phosphorus. Magnesium Deficiencies Bottom leaves are affected first but new leaves soon follow. Old leaves show interveinal chlorosis Puckering of the leaf surface is sometimes seen along with rapid leaf drop.

48 Iron (Fe) Generally found in most soils but can be tied up on alkaline soils. Symptoms show on young leaves first. Iron Deficiencies Leaf show yellowing between the veins with the veins staying green (call iron chlorosis). In severe cases, leaves turn whitish and then can blacken. Eventually, shoot tips may die.

49 Zinc (Zn) Tied up in highly alkaline soils and can also be leached in sandy soils. Mottled yellow spots occur Zinc Deficiencies Small leaves es form, rosetting at tips of plants, short internodes

50 Fertilizers Over fertilizing can be detrimental to the health of your plants, can increase pest problems, can result in pollution to the environment and can adversely affect the health of the soil ecosystem. Use a soil analysis, leaf analysis, or look for nutrient deficiency symptoms to adequately determine plant nutrient requirements. Timing fertilizer applications to season growth and applying the proper nutrient ratios can maximize the health and performance of your fruit trees.

51 Timing Fertilizers to Seasonal Growth Apply a balanced fertilizer to promote growth, and fruit production. Apply low nitrogen-higher phosphorous fertilizer in mid fall to promote root growth, flowering and fruit production in Spring. Apply a mild nitrogen fertilizer to promote a last flush of growth after the heat of Summer is over.

52 Pest Control - Ants Ants farm many honeydew producing insects. Controlling ants and keeping them out of your trees can greatly help to reduce insect pest problems. Ants can be kept out of trees by banding tree trunks with sticky substances such as Tanglefoot. Trim branches to keep them from touching structures or plants so that ants are forced to climb up the trunk to reach the foliage. Protect young or sensitive trees from possible injury by wrapping the trunk with a collar of heavy paper, duct tape, or fabric tree wrap and coating this with the sticky material. Check the sticky material every few days and stir it with a stick to prevent the material from getting g clogged with debris and dead ants, which will allow ants to cross.

53 Ants When properly p used, baits are more effective and safer than sprays or granules to control ants. Bait products must be slow-acting so that the foraging ants have time to make their way back to the nest and feed other members of the colony before they are killed. Ant baits contain either carbohydrates (e.g., sugars), proteins, or oils, or some combination of these as attractants along with an active ingredient (toxicant). Different attractants are more effective against different species of ants and at different times of the year. In the case of Argentine ants, sweet baits are attractive year-round. Protein baits are attractive ti primarily il in the spring because they are brought back to the colony to feed the developing brood. Offering a small quantity of each kind of bait and observing which one the ants prefer is a good way to determine what to use. Control with baits may take several weeks or more to be complete.

54 Pest Control Tolerance to low levels of plant pests is a key ingredient to successful pest control. When pest numbers become large and damage to your plants becomes unacceptable, control measures often become necessary. Proper timing is essential for control measures to be successful! Most soft bodied insects can be controlled by using insecticidal soaps. Soaps also help to clean your trees and remove honeydew, sooty mold, and dirt and dust.

55 Many sucking insects produce large quantities of a sticky excrement known as honeydew, which often turns black with the growth of a sooty mold fungus. Sooty Mold Sooty mold blocks sunlight and reduces photosynthesis.

56 Pest Control Most pest control products used on fruit trees are contact killers. They kill what they touch. The key to successfully using pest control products are to be complete and thorough with your applications and to be consistent with your follow up applications!

57 Aphids Aphids affect nearly all fruit trees. They occur primarily on young foliage and shoot tips. Large populations of aphids cause curling, yellowing, and distortion of leaves and stunting of shoots. This may affect growth to the point of hampering the development of fruiting wood and tree development. Damage caused by Green Peach Aphids Aphids (as well as other sucking insects like soft scale and whitefly) can produce large quantities of a sticky excrement known as honeydew.

58 Aphids Aphids have many generations a year. When the weather is warm, many species of aphids can develop from newborn nymph to reproducing adult in 7 to 8 days. Because each adult aphid can produce up to 80 offspring in a matter of a week, aphid populations can increase with great speed. High levels of nitrogen fertilizer favor aphid reproduction.

59 Aphids A few aphid species attack parts of plants other than leaves and shoots. The woolly apple aphid infests woody parts of apple roots and limbs, often near pruning wounds, and can cause overall tree decline if roots are infested for several years.

60 Pear Sawfly (Pear Slug) Host specific. Plants commonly attacked: Pears, plums, cherry. Larvae feed on leaves causing a windowing effect. Damage may cause reduced vigor g y g from loss of leaves.

61 Green Fig Beetle Plants commonly attacked: Fig, soft fruit.

62 Green Fig Beetles Large grubs (larvae) are frequently found in compost piles and in soil that is rich in organic material. Traps hung in trees during the summer can help reduce Fig Beetle populations and can help to reduce damage to the crop.

63 Codling Moth The larvae of the codling moth (Cydia pomonella) )is the common apple worm. It attacks apples, pears, quince, walnuts, and other tree fruits. Codling moth adults are about 1/2 to 3/4 inch long with mottled gray wings that are held tentlike over their bodies. Their appearance blends well with most tree bark, making them difficult to detect. Codling moths can be distinguished from other moths by the dark, coppery brown band at the tip of their wings. Codling moths overwinter as full-grown larvae within thick, silken cocoons under loose scales of bark and in soil or debris around the base of the tree. The larvae pupate inside their cocoons in early spring and emerge as adult moths mid-march to early April. After mating each female deposits 30 to 70 tiny, discshaped eggs singly on fruit, nuts, leaves, or spurs. After the eggs hatch, young larvae seek out and bore into fruit or developing nuts.

64 Codling Moth After completing development they leave the fruit and drop from the trees to search out pupation sites and continue the life cycle in the soil or on debris under the tree; some crawl back up the tree to pupate in bark crevices. The rate of development will vary with temperature, proceeding more rapidly in warmer weather and climates. Depending on the climate, codling moth can have two, three, and sometimes four, generations per year. Trapping the adults can help to control this pest. Traps can also help time pesticide applications. BT and spinosid are somewhat effective if applied before the larvae chews into the fruit.

65 Oriental Fruit Moth The Oriental fruit moth (OFM), native to China, was introduced to the United States from Japan about 1913 on infested nursery stock. The OFM is now found in all regions of North America where peaches are grown. Although it is most important as a pest of peach, the OFM has an extensive host range that includes apple, quince, pear, plum, cherry, apricot, nectarine, and some rosaceous ornamentals. The moths overwinter as full-grown larvae in cocoons in tree bark crevices, weed stems and trash on the ground. In the spring, the larvae change into pupae. The adults begin to emerge about the time peach blossom buds show pink. It may have five to six generations per year. The larva attacks the twigs and fruits of most host plants.

66 Oriental Fruit Moth When the terminal parts of rapidly growing twigs are succulent, they are frequently attacked by the Oriental fruit moth. Succulent peach twigs are exceedingly attractive to the larvae. Plum, apple and cherry may occasionally be moderately infested. One larva may enter two to five twigs or even more. Young trees are usually more heavily attacked than old bearing trees. One larva may enter two to five twigs or even more. A full-grown larva will emerge from a twig and seek a place to spin a cocoon. In peach fruit, two distinct types of injury are visible. One is caused by feeding on or entrance into the side of the fruit early in the season when the fruit is small. Frequently called "old injury," this is usually caused by larvae that have abandoned the twigs and gone to the fruit. Injury caused by entrance at the stem, sometimes called "new injury," occurs when the fruit is almost full grown. This injury is caused by newly hatched larvae that go directly to the fruit. When a larva has completed its development in a peach it tunnels to the surface and When a larva has completed its development in a peach, it tunnels to the surface and leaves the fruit through a clean hole.

67 Shothole Borer The shothole borer is a serious pest of many deciduous fruit and nut trees, including stone fruits, apples, pears, and almonds. Adult borers are tiny bullet-shaped, reddish black beetles about 0.10-inch long. Female shothole borers bore small holes, which look like shot holes, in the bark and lay eggs in a gallery 1 to 2 inches long running lengthwise down the cambium layer of the tree. Hatching larvae feed and excavate secondary galleries at right angles to the egg gallery, creating a gallery system that looks like a centipede. Larvae spend the winter in their galleries beneath the bark. Two or three generations occur a year in California.

68 Shothole borers can and do kill trees. Once a tree has been seriously attacked, there is often no way to save the tree. Systemic insecticides such as imidacloprid can be beneficial if used before extensive damage occurs. Borers often attack stressed trees. Keeping your fruit trees healthy is the best way to prevent this pest. Healthy, vigorous trees can often defend themselves from minor borer attack. Dormant sprays do not control borers. Shothole Borer

69 Peach Twig Borer Larvae bore into the growing g shoots of twigs and ripening fruit or nuts. Shoots and leaves wilt and die back one to several inches from the growing tips of twigs. In fleshy fruit, injury is usually superficial. Spraying during the growing season is difficult to time pesticide applications effectively. Sprays must be applied to control hatching larvae before they enter twigs or fruit. In the fall, winter, and very early spring, peach twig borers overwinter in limb crotches in cells called hibernacula covered with chimneylike piles of frass and sawdust. Larvae emerge in early spring and migrate up twigs and branches, where they attack newly emerged leaves and shoots. Pupation takes place in protected t places on trees and occasionally in the stem cavity of infested fruit. Ad lt l ti i di id ll t i d f it i Adults lay tiny eggs individually on twigs and fruit in the spring and summer and on young branches in the fall.

70 Root Knot Nematodes Root knot nematodes attack a wide range of fruit trees. Root knot nematodes are difficult to control and can be spread easily from garden to garden in soil (for example, on tools, boots, etc.) and plant parts. Root knot nematodes survive from season to season primarily as an egg in the soil. After the eggs hatch, the second stage juveniles invade roots, usually at root tips, causing some of the root cells to enlarge where the nematodes feed and develop. Root knot nematodes usually cause distinctive swellings, called galls, on the roots of affected plants. The nematodes feed and develop within the galls, which may grow to as large as 1-inch in diameter on some plants but are usually much smaller. The water- and nutrient-conducting abilities of the roots are damaged by the formation of the galls.

71 Root Knot Nematodes Above ground symptoms of a root knot nematode infestation include wilting, loss of vigor, yellowing, and other symptoms similar to a lack of water or nutrients. Fewer and smaller leaves and fruits are produced, and plants heavily infested early in the season may die. Damage is most serious in warm, irrigated, sandy soils. Some control may be achieved by using fruit tree rootstocks that are resistant to nematode injury, increasing the organic material in the soil with the use of mulches or soil amendments, or by introducing beneficial Steinernema feltiae (Sf) nematodes.

72 Snails and Slugs Snails may lay eggs up to six times a year. It takes about 2 years for snails to mature. Snails are excellent climbers and often will also feed on foliage and fruit of some trees; citrus are especially susceptible to damage. The brown garden snail (Helix aspersa) is the most common snail causing problems in California gardens; it was introduced from France during the 1850s for use as food. The white garden snail, Theba pisana (Mueller), is the worst potential agricultural pest of the helicid snails introduced to North America The snails were found and identified in August 1985 in San Diego, California, at several localities in about a 10 square mile area

73 Snail and Slugs Most snail and slug baits have Baits containing Iron Phosphate kill mateldehyde as the main snails and slugs but are of very low active ingredient. risk to dogs, cats, wildlife and people. They are also less toxic to fish than conventional snail baits. Mateldehyde is very toxic to mollusks as well as dogs, cats, wildlife, fish and people. As these baits break down they become plant nutrients in the form of iron and phosphorous.

74 Snail and Slug Control Snails and slugs cannot crawl over copper.

75 Birds Many birds eat insects in the garden, however, some also eat ripening fruit. Birds should be discouraged from you fruit, but never harmed or killed. There are several products available to protect your crop from birds. Scare Tape

76 Birds The most effective bird deterrents are nets. Any size net which completely l encloses the tree will be effective against birds. 1/4" mesh bird net from Bird-B-Gone is a solution for both birds and Fig Beetles.

77 Pests and Diseases Pocket Gophers Fruit tree roots are a favorite food of gophers, who can easily kill a large plant. One passive method of control is to plant the tree in a large aviary wire basket. The wire should have openings no larger The wire should have openings no larger than ½ and the top edge of the basket should extend at least 2-3 above the surface of the soil.

78 Gopher Control Products Traps, Baits and Gases Important in the effectiveness of these products is that they should be placed in a fresh tunnel or run. Traps are often the most effective. Use in pairs and placed back to back. Baits work well if used properly. A bait injector tool is a useful tool. Gases are most effective when the soil is moist. Gases are often the least effective of these options.

79 Peach Leaf Curl Fruiting plants affected by Peach Leaf Curl are limited to Nectarine and Peach. Symptom appear on leaves in spring. Likes cool, wet weather below 80 degrees. Leaves fall off as temp get hot. May damage twigs & shoots causing them to die.

80 Peach Leaf Curl Taphrina deformans Peach leaf curl affects the blossoms, fruit, leaves, and shoots of peaches and nectarines, and is one of the most common disease problems for backyard gardeners. When severe, the disease can reduce fruit production substantially. Leaf curl first appears in spring as reddish areas on developing leaves. These areas become thickened and puckered, causing leaves to curl and severely distort. The thickened areas turn yellowish gray and velvety as spores are produced on the surface by the leaf curl fungus. Affected leaves later turn yellow or brown and can remain on the tree or may fall off; they are replaced by a second set of leaves that develop more normally unless wet weather continues. The loss of leaves and the production of a second set result in decreased tree growth and fruit production. In addition, defoliation in spring may expose branches to sunburn injury. The leaf curl pathogen also infects twigs and shoots. Affected shoots become thickened, stunted, distorted, and often die. Only rarely do reddish, wrinkled areas develop on fruit surfaces; later in the season these infected areas become corky and tend to crack. If leaf curl infection builds up and is left uncontrolled for several years, the tree may decline and need to be removed. It takes about 2 weeks after leaves emerge from buds before leaf symptoms appear.

81 Peach Leaf Curl Taphrina deformans The fungus survives the hot, dry summer on the tree s surfaces.. In spring, the fungus is moved by splashing water and can infect newly developed leaves. To prevent peach leaf curl, treat peach and nectarine trees every year after leaves have fallen. Copper-based fungicides, calcium polysulfide, or synthetic fungicides can be used. To be effective, copper-containingcontaining compounds must have at least 50% copper. It is be advisable to apply a second treatment in spring, preferably before buds begin to swell, but definitely before bud break (when green color is first visible). Although symptoms of leaf curl are seen primarily in spring as new leaves develop, there is little you can do to control the disease at this time. Normally, diseased leaves fall off within a few weeks and are replaced by new healthy leaves unless it is rainy. Development of leaf curl ceases when young tissue is no longer developing or when weather turns dry and warm (80 to 85 F). If leaf curl symptoms occurred on your trees in spring, be sure to treat the following fall, around mid December, to prevent more serious losses the next year.

82 Coryneum Blight (Shot-Hole Fungus) Fruiting plants affected by Coryneum Blight : Almond, Apricot, Cherry, Nectarine, Peach, Plum. Affects leaves, fruits, buds, blossoms & twigs. May kill buds, cause blossom blight, shot-hole symptoms in leaves, cause twig cankers that may kill a branch. Gumming is common around infected buds & cankers. Spots on fruit become hard & rough with dry corky areas underneath.

83 Coryneum Blight (Shot-Hole Fungus) Reddish or purplish brown spots about 0.10 inch in diameter occur on new leaves and shoots. The spots expand and their centers turn brown. Tiny, dark specks sometimes form in the center of lesions, especially on leaves. Spots on young leaves have a narrow, light green or yellow margin and their centers often fall out as leaves expand, leaving "shot holes." Buds of peach, nectarine, and sometimes apricot are killed in the winter. Fruit may become rough and corky. Spotting occurs on the upper surface. Concentric lesions may develop on branches. The fungus that causes shot hole survives the dormant season inside infected buds and in twig lesions. The spores produced on lesions can remain alive for several months. They are spread by splashing rain or irrigation water. Spores that land on twigs, buds, blossoms, or young leaves require 24 hours of continuous wetness to cause infection. Only the current season'ss growth is susceptible to infection.

84 Brown Rot Fruiting plants affected by Brown Rot include stone fruit (Apricot, Cherry, Nectarine, Peach, & Plum) and Citrus. Infection consumes entire fruit as fruit ripens. Likes high humidity & warm temp Citrus infection start as soft leathery areas and develops an odor. Skirt lower branches to aid in preventing spread from spores in ground

85 Brown Rot Pathogens: mostly Monilinia fructicola and M. laxa Ripe fruit rot caused by Monilinia results in firm, circular spots that spread rapidly over fruit. Monilinia causes dark brown lesions on fruit that eventually turn black from the development of pseudosclerotia (fungal tissue), Fruit with brown rot infections are shriveled and develop powdery tan masses of spores. Individual fruit may be infected, but rotted fruit usually occur in clusters that are stuck together. Injured fruit and fruit that touch each other are the most susceptible to brown rot infections. When Monilinia-diseased fruit remain on the tree, they are known as mummies. Removing or turning under thinned fruit helps reduce fruit brown rot. Thinned fruit can be a source of inoculum for brown rot on ripening fruit, especially if they are left where they will come in contact with irrigation water. Fungicides are preventive, not eradicative; they must be applied to uninjured fruit before infections occur. Injured fruit cannot be protected from rot caused by Monilinia