Hickory orchards require cultivation management and pest control
1 Ecological characteristics of pecans
Hickory trees are deep-rooted fruit trees, requiring deep and fertile soil, like warm and humid climate, semi-positive plants, adapted to the soil ph value between 5.5 ~ 7.0, with 6 ~ 7 is the best, planted in the low mountains at an altitude of 200 ~ 800m, adult trees can produce abundant and stable yields. The propagation of hickory trees is mainly based on sowing seedlings, and can also be cut with 1 to 2 years old branches, transplanting and colonization are generally carried out after the fall of leaves in autumn to before the spring of the following year, but spring planting should be sooner rather than later. Pecans are wind-borne flowers, and rainy, windy or low temperature weather is not good for pecan pollination and fruit setting. Hickory tree body is tall, strong dryness, the top bud and nearby buds are easy to extract, the middle and lower parts of the germination force is weak, in order to promote the early fruit of young trees, the backbone branches can be appropriately shortened. Hickory trees grow slowly in their infancy, and gradually accelerate after 3 years of growth, generally starting to bear fruit in 5 years and entering the full fruit stage after 10 years. Pecans have obvious large and small annual phenomena, and cultivation management techniques are particularly important to obtain stable and high yields.
2 Hickory gardening requirements
Hickory orchards should choose a gentle slope in the mountainous area at an altitude of 300 to 800m, requiring deep and fertile soil, good drainage, leeward to the sun, limestone,
Mountain soils with shale and granite development can be planted, but areas with low-lying water and excessively sticky soils are not suitable for planting. High standards of land preparation are the basis for ensuring high quality and high yield of pecans. The best way to prepare land in mountainous areas is to build terraces, and where the soil conditions are poor, troughs are also used to change soil. Pecans are suitable for dense cultivation, and 40 to 50 plants per 667m2 are more suitable, and can be used for 4.5m×3.5m or 4.0m×3.3m. Planting is divided into autumn planting and spring planting, during this period as early as possible to improve the survival rate, generally autumn planting is higher than the spring planting survival rate. Pecan seedlings require pure varieties, complete primary and lateral roots, no pests and diseases, strong stress resistance, preferably 2 to 3 years old seedlings. When planting, the root system is first trimmed to break the root segments and overly long roots, leaving 80 cm in the upper part to dry. When planting, the root system is layered with fine soil and then watered through the root water, and the effect of using 0.4% urea + 0.4% potassium dihydrogen phosphate mixed fertilizer as the root water will be better. The depth of planting of seedlings can be slightly higher than the depth of the original seedling, but the grafting interface must be exposed outside, and immediately after planting, it is watered once permeable.
3 Management techniques for the cultivation of pecans in abundance
3.1 Soil management
Soil management in hickory orchards is crucial and is an important part of ensuring stable yields. For juvenile hickory orchards, dwarf crops such as vegetables and beans can be planted intermittently, and green manure plants such as clover and purple cloud can also be planted, which can obtain economic benefits, inhibit weeds, mature soil, and facilitate the rapid growth of young trees. Do not plant tall crops such as corn and sunflowers, as well as climbing plants such as pumpkins, so as not to affect the growth of hickory trees. At the same time, the use of corn and other crop straw to cover the hickory orchard can not only inhibit weeds, reduce the cost of manual weeding, but also increase the content of soil organic matter to achieve the purpose of improving the soil.
New young pecan orchards should be turned over once a year or every other year. It is advisable to extend 40 to 50 cm and a depth of 60 to 70 cm along the outer edge of the canopy, and bury straw, green manure, etc. for covering to mature the soil and enhance soil permeability. Adult gardens can be combined with fertilization for deep turning, and buried in organic fertilizer, weeds, crop straw, etc.
3.2 Shaping trimming
3.2.1 Shaping When the pecan young tree grows to 80 cm, pick the heart in time, select 2 to 4 strong buds with different directions for the main branch culture after germination, and wipe all other buds near the main branch culture buds so as not to affect the growth of the main branch buds; when the main branch grows to 40 cm, pick the heart, and after branching, select 1 front bud to prolong the growth of the branch, and select 1 bud for side branch culture; when the side branch grows to 30 cm, the heart is picked when the extension branch grows to 45 to 50 cm; the method of piling with rope is used to pull the main branch to make the distribution direction of the main branch even
。 Shoots that extend the growth of branches and side branches are not affected, and are erased or left according to their density. The main task of the management of 3 to 4 years of tree age is to do a good job in water and fertilizer management, accelerate the growth of the tree, promote the formation of a favorable tree shape as soon as possible, and lay a good foundation for future harvests. Generally, all female flower buds are removed in the spring of the second year to avoid premature fruit setting, affecting the growth of the tree, and 10 to 20 fruits can be borne according to the condition of the tree in the fourth year.
3.2.2 Pruning First, on the basis of the previous year, cultivate 1 side branch, so that each main branch has 2 side branches and 1 extended branch. The first branch is 40 ~ 45 cm from the main trunk, and the second side is 50 ~ 55 cm from the first branch, which is completed by cutting the heart and pulling the branches. The second is to cultivate fruiting branches on both sides of the side branches, extension branches and main branches, and use pruning techniques such as heart picking and twisting to make the resulting branch groups of different sizes fill the tree body space. As a result, the principle of branch configuration is that the inside is large and the outside is small, the inside is dense and the outside is sparse, the size is staggered, the density is not crowded, and the sparse is not empty.
3.3 Fertilization management
In order to achieve the purpose of premature birth, abundant yield, high quality and high efficiency, it is necessary to strengthen the fertilization management of pecans, and the balanced fertilization of whole nutrition is the key. It is necessary to re-apply organic fertilizer, rationally apply chemical fertilizer, match medium and trace element mineral fertilizer, and apply biological bacterial fertilizer. If the soil is too acidic or barren, it is also necessary to apply soil conditioners scientifically. Chemical fertilizers should be applied in accordance with the principles of nitrogen reduction, phosphorus stabilization and potassium increase, and foliar fertilizers can be sprayed at the same time. Hickory fertilization is carried out according to the principle of "setting the yield with the tree and fixing the fertilizer by producing the fertilizer". In general, young trees less than 5 years old are subjected to organic fertilizer at about 10 to 20 kg, and nitrogen, phosphorus and potassium are applied to chemical fertilizers in the ratio of 5 : 1 ∶ 1 to 1. 6 ~ 10 raw hanging fruit walnut tree, each production of 100 kg of fruit needs to be applied 100 ~ 150 kg of organic fertilizer, pure nitrogen 1.7 kg, nitrogen, phosphorus, potassium ratio of 5 : 2 : 1. Generally, the fertilization amount of early fruit pelar should be higher than that of late fruit pelar, 1 to 10 years old trees, the annual fertilization amount is nitrogen, phosphorus, potassium ratio of 5 ∶ 2 : 2, organic fertilizer 250 kg. Adult trees should appropriately increase the amount of phosphorus and potassium fertilizer, nitrogen, phosphorus,
The potassium ratio is adjusted to 2: 1 : 1 to improve fruit quality.
4 Pest control
4.1 Disease control
Pecans have relatively few diseases, and common ones are rot, blight, powdery mildew, brown spot disease and black spot disease.
4.1.1 Rot disease In early spring and the growing season, the disease is thoroughly scraped in time, and the old bark should be scraped off by the big tree to remove the scar hidden under the cortex. After shaving, disinfect the wound with 50% methyl tolbuzin wettable powder 50 accompanying solution, or 50% antibacterial special wettable powder 50 times liquid, and then apply Bordeaux liquid.
4.1.2 Branch blight Select 70% methyl tolbuzin wettable powder 800 ~ 1 000 times liquid, or 400 ~ 500 times liquid of Daisen manganese zinc wettable powder spray control, spray every 10 days once, spray 3 to 4 times can achieve obvious control effect.
4.1.3 Powdery mildew endangers leaf shoots and shoots, causing early defoliation and even the death of seedlings. At the beginning of the disease, triazolone 3000 times liquid can be sprayed.
4.1.4 Brown spot disease mainly harms leaves, fruits and young shoots, and is infected many times a year. Spray 1 : 2 ∶ 200 times Bordeaux liquid or 500 to 800 times liquid of 50% methyl tolbuzin wettable powder once before and after flowering and in mid-June.
4.1.5 Black spot disease This disease is caused by a pathogenic bacterium, also known as walnut bacterial black spot disease. Spray 3 to 5 pomerite sulfur compounds before germination, spray 1 : 2 ∶ 200 Bordeaux liquid or 50% methyl tolbuzin wettable powder 500 to 800 times liquid before germination, and spray once before flowering, after flowering and once at the young fruit stage of female flowers.
4.2 Pest control
The main insect pests of pecans are small giddings, inchworms, weevils, stinging moths and walnut flatleaf beetles.
4.2.1 Walnut Giddings During adult occurrence, spray 25% ceivine wettable powder 500 times liquid, or 2.5% cypermethrin emulsion 4000 times liquid control.
4.2.2 Wood mantis inchworm Especially in the peak stage of insect feathering and larval infestation, the tree body spray 25% wettable civiine powder 300 ~ 500 times the liquid control effect is better.
4.2.3 Walnut fruit weevil Pick up fallen fruits or remove the affected fruit in time to eliminate larvae and feathered adult insects. When insect infestation occurs, spray 2.5% cypermethrin emulsion 2000 ~ 3000 times liquid control.
4.2.4 Thorn moths are also known as yangraz, octagons. Taking advantage of the phototropic habits of adult moths, insect traps are set up to trap adult insects during the peak period. During the larval occurrence period, 50% borer pine emulsion, 10% Uranus emulsion 5000 times liquid, 2.5% rotenone 300 ~ 400 times liquid and other control.
4.2.5 Walnut flat leaf beetle Also known as walnut leaf beetle, whole flower worm. During the overwintering period of the eggs, remove the dead branches, leaves and weeds in the walnut orchard and bury them deeply in time. When large-scale severe occurrence, spray 5% cypermethrin emulsion 3000 times liquid, 2.5% kung fu emulsion 3000 times liquid and other prevention and control.