Walnut is of great economic importance, because of its large trees perform water protection, soil protection and water regulation functions, and are ecologically important plant object.
walnut trees compared with other fruit crops are characterized by their durability and regularity of fruiting.Meets trees aged 200-300 years.According to NVSorokin, in the Crimea - Bajdarsky Valley - growing walnut tree , whose age was determined in 1,000 years.
Walnut - deciduous, monoecious with dioecious flowers, cross and wind-pollinated.Male and female generative organs are located on the same plant, but separately.
walnut leaves are large, compound, imparipinnate, with 5-9 smooth-edged leaves from elliptic to ovate, dark green, at the edges slightly serrated, with a specific smell.There are also simple leaves, t. E. Having one plate and cutting, as well as two and four leaves.
kidneys are divided into vegetative and reproductive.By vegetative buds are forming leafy shoots of growth that can be lateral, located
Staminate kidney, t. E. Men have an elongated conical shape and 1.5 cm long, are brown-brown color with numerous spirally arranged scales, like the facet structure.The flowers are placed in direct earrings that at puberty reach 15 cm in length and 1.5 cm in diameter and are fruitful escape past, in its lower part and a 1-2 together.The flowers at the base of earrings have 20-30 stamens, and in the upper part of the same earrings -6-8 only stamens.First blooming flowers are at the base of earrings, then at the top.
Staminate flower consists of three bracts, fused basally.stamens is in the center of the hull.Each stamen consists of a short thread attached to the hull, courier, on which the anthers.The anthers of the stamens have elongated shape and in maturing pollen opened on the sides of the longitudinal slots.Matured pollen spreads like wind and bees and bumblebees.Period flowering staminate flowers up to 20 days.The differentiation of the stamen of the kidneys occurs during the growing season and ends in May or June.
Pistillate flowers appear on this year's escape and arranged singly, 2-3, and harvest year - 4-5 at one pedicel.There are varieties and walnut shape in which flowers are collected in the brush 2 and more flowers.Pistillate (female) flower - elongated shape, the top of the switches in a column and terminates in two large shirokobahromchatymi stigmas light, pinkish-yellow color.Blooming pistillate flowers soon after the beginning of shoot growth and the appearance of 3-4 leaves in time, which in our climate is at the end of April - beginning of May.Female flowers retain sensitivity to pollen for two weeks.Differentiation, t. E. Laying and formation of pistillate flowers, always takes place in the embryonic cells of the apical or adjacent cells with them.This process begins in the fall and ends in the spring.
As a rule, on the same tree flowering staminate and pistillate flowers occur at different times.This phenomenon is called dichogamy.Therefore, in industrial gardens tab should be selected varieties of pollinators.A number of varieties and forms of first bloom stamen flowers, this type of flowering is called protoandrichesky type.
Due to the fact that pollen for a long time retains susceptibility, female flowers are pollinated by pollen of its same wood.According to Y.Nikitinsky compared with open pollinated selfing significantly increases yield - 40%.This phenomenon, called gomogaliey, very rare.
When nedoopylenii flowering period increases, and protogenichnyh forms of self-pollination occurs that is excluded in most cases protoandricheskih forms.This explains the fact that protogenichnye form more productive than protoandricheskie, and that both forms of increased productivity at the coincidence of the timing of flowering.
There are cases when the appearance of the fruits of some varieties and forms occur without pollinators, ie apomictically.Identification and implementation of apomictic forms walnut year allows to obtain high yields of nuts and guaranteed regardless of the conditions at the flowering period.
walnut pollen is light and nutritious.It consists of 23% protein, 14% sugar, 32% fat, 4% water and 3% ash.In this regard, during flowering hazel pollen attracts a huge number of bees.As a result of research conducted by scientists, found that pollen walnut compared with other fruit crops is the easiest and, according to smoking, a long time she hovers in the air, flying at a distance of 8 km.
flowering type is not an inherited trait in the offspring and appears at the seed multiplication in almost equal proportions and protoandriya Protogenov.
takes into account features such as the type of flowering samoplodnye degree, the selection of pollinators, the nature of fruiting.All these factors strongly influence the productivity of walnut stands.
Pistillate flowers on a walnut tree appear before the stamen, which are laid in the majority only on 4-6 th years depending on the characteristics of varieties and forms.
exception is the number of varieties of the "ideal", on which there is a secondary bloom.
type of fruiting is also an important biological feature of this culture.Most of the varieties and forms of fruit of the apical buds;same side (axillary) buds they are by growth.However, there are trees that are capable of bearing fruit as the apical and lateral to the kidney (apex-side type fruiting).Such forms and varieties have a higher yield and a more moderate growth.Fruits walnuts placed one by one, but more often 2-3 fruit and sometimes reaches the number 4. There are a variety acinar fruiting (8-15 fetuses).
Walnut can be successfully grow on soils of different fertility, including the poor in humus, sand and skeletal, with neutral and alkaline reaction.These soils are black earth, forest type loam, sandy loam black earth, preference is given to a deep, loose, alluvial soils and fresh.The highest productivity of walnut reaches the relatively rich and well drained, and the first alluvial terrace soils river valleys.These soils should include (but on the territory of our region more than 600 varieties of soil) black soil all subtypes and species, including: light gray, gray, dark gray, meadow, floodplain meadow and chernozem-meadow soils.Good walnut trees grow on calcareous soils.
In all cases it is necessary to avoid wetlands and soils with shallow groundwater (no closer than 2-4 meters).The main indicator of the suitability of land for the walnut is the volumetric weight of the soil, which must be less than 1.45 g / cm3 at a depth of 60 cm.
on eroded slopes and poor, heavy, clay soils walnut grows very slowly, early aging and practically does notcrops.
necessary condition for good growth of trees is a soil moisture.Excessively wet, marshy soil type, as well as very dry soils are not suitable for the growth of walnut.It is resistant to air drought, but it is particularly sensitive to groundwater and salinity, including toxic salts.
Walnut related to species, withstanding cold-cool river bed flooding, within one month.The nut garden, located in a valley, out of every 2 to 5 years are barren because of spring frosts.
Walnut love of light and heat-loving.
critical temperature for walnut - 27 degrees below zero.When the cold - 25, 27 degrees and damaged male catkins of the vegetative buds, at 28, 29 degrees annually with p east, 30 degrees - skeletal branches and the whole tree to the level of the root collar.Skeletal branches are damaged, usually from the south side, forming a severe burns on the trunk bark.
bark of young trees, light gray, later with big cracks.
weakest resistance to low temperatures have roots that must be considered when spring planting nut trees, as well as digging seedlings and during storage.Loose tissue damaged by the roots of 5-6 degrees below zero, and it can lead to complete destruction of the plants.
Despite the fact that the walnut is a heat-loving, the air temperature rise in summer above 37 degrees causes significant damage to the fruit, placed in the crown of the tree.When sunburn fruit suspended in the development and formed small withered kernels.
The growing season of blooming walnut (March) kidney prior to leaf fall (October-November) in our situation is different in the years from 180 to 210 days.
Walnut does not tolerate shade.This explains that the single standing crop or discharged he develops a strong crown and root system and provides regular and abundant harvests.Shaded as the plants grow and bear fruit worse.Weak due to shading of the skeletal branches affected by low temperatures, diseases, pests and subsequently dies.Therefore, pruning is mandatory agricultural practices in the technology of cultivation of this crop.
At a young age, when the trees are bright, they have a great ability to pobegoproizvoditelnoy.The absolute number of kidneys at the conductor and skeletal branches go to the growth, form a one-year increments, which are the consequence of turning into skeletal branches.Trees left without trimming (8-10 year olds), we can count up to 20-30 of the skeletal branches of the first order.
With strong blackout usually occurs only apical shoot growth, ie,apical bud grows only very rarely one or two sides.Consequently, in the 12-15 age krona consists of a plurality of elongated and skeletal bare branches and underdeveloped sheet unit and the crop will be available only on the periphery of the crown.
The most common way of forming a cup-shaped walnut crown with 3-4 skeletal branches and the change-leader form of the crown with 5-6 skeletal branches.
In the formation of the trees on the cup type in the zone laid kronirovaniye 3-4 first-order branches having good fusion and arranged evenly.The distance between the branches should be at least 60-80 cm tab of the skeletal branches finish in the 3-4th year after planting, and then remove the center conductor.For optimal illumination inside the crown skeletal branches are cut by transferring onto the underlying branch.Later pruning produce mainly for the purpose of removing the sick, injured and shading crown branches.
change-leader Forming is as follows: skeletal branches and laid singles, but the first two, if they are in opposite directions, it is necessary to lay out related kidney.During the 1-year growth of seedlings form a 3-4 shoot and therefore to the formation of the crown should begin in the 2nd year.The process to create the desired structure occurs within 5-6 years, and is considered complete, are 5-6 branches of the first order, from which it follows form the branches of the 2nd and following orders.Further
the central conductor act in the same way as in the cupped formirovke ieremoved.Subsequently produce thinning shaded, sick, injured and withering branches.
As wood is a natural aging samoizrezhenie crown.First, dry loose, damaged by frost, pests and diseases branch.On the old tree is not more than 4-5 branches of the first order.
Thus, the walnut tree can form a powerful crown, capable of laying and holding a big harvest, when appropriate, by the forming of the crown provides good lighting.
Walnut - a fast-growing breed, having a great ability pobegoobrazuyuschey, especially at a young age in the conditions of optimum soil and climate regime.When sowing a plant walnut walnut saved taproot, resulting in increased winter hardiness.Transplant nut should not be without pereshkalivaniya, especially graft material.
In the first year of life walnut seedling can reach a height of 30-50 cm, and in exceptional circumstances, and above, 1 cm in diameter.The root of the period becomes 5/4 times the length of the barrel.In the second year of life increases seedling growth, and by the end of the growing season it reaches a height of 1 meter to 6 years of age - 2.5 meters, in the 60-80 age - 15 to 20 meters.
The root system of a walnut, unlike other fruit crops, devoid of suction hair.The process of absorption of mineral substances in aqueous solution performs mycorrhiza symbiosis between soil microbes and tree roots, and therefore when planting trees necessary binding organic fertilizers, which contributes to the rapid formation of microflora in the root area, and consequently a better development of a root system andthe underground part.
active growth taproot lasts only 3-5 years and reaches this time 3-3.5 m depth.At the age of 20-30 years, the penetration depth of the taproot reaches 6.5-7 meters.With age, the lateral roots thicken much, and their distribution range sometimes reaches more than 20 meters.When the excavation of the root system of the tree walnut 55 years of age (in the planting along the irrigation canal) found strong lateral roots up to 25 cm at the base, which grew in the direction of the channel.The old tree roots spread range is 3-4 times greater than the radius of the crown.The powerful development of the root system of a walnut stick-type contributes to its high wind resistance and winter hardiness.
Only in cases of unilateral or superficial root development on eroded soils under the mountain slopes there is windfall walnut trees.The adverse impact of the ever blowing winds in one direction adversely affects the walnut trees.For example, in Sochi and Tuapse areas, according to AIGolikova, walnut growing on mountain slopes, different weak resistance to the wind, because of one-sided and superficial development of its roots.
following during flowering intense dry winds adversely affect the process of flowering, pollination and fertilization of flowers.All of this highlights the need for concentration of nut plantations, including industry, in places, well protected from the winds.Normal good gain walnut shoots of young trees in the North Caucasus from 60 to 100 cm and 1 cm in diameter.In wet years, the increase is 200 cm during the growing season.Walnut, compared with other fruit crops, and has a high pobegoobrazovatelnoy pobegovosstanovitelnoy capacity.
Shoots respectively divided into growth and fruitful.At growth of shoots one growth cycle during the growing season.Normal growth of their ends in mid-July.Stems smooth, shiny.
growth walnut shoots occurs most rapidly in the first half of summer fruits - in the first month after flowering, and in early July terminated.In the future, growing green shell and kernel matures.In the second half there is a temporary attenuation of the primary meristem of shoots on an intensive growth in thickness.The second half of the growth characteristic of this culture, and it usually ends in August in relation to our conditions.In some, especially moist and warm years, this period is prolonged, there is a danger of damage growing shoots in early autumn frosts.
Vigorous growth walnut continues to 40-50 years.It then gradually attenuates, the increase in thickness continues throughout the life of the tree.
low level of agricultural techniques often leads to a lengthening of the tree growth period before the entry into fruition, t. E. Early appearance of fruit, in premature reduction in the growth of the activity, as well as dried out and ruin it.