Soil Management measures of Chestnut Orchard in Yanshan

Soil Management measures of Chestnut Orchard in Yanshan

Yanshan chestnut orchard is mostly built in mountainous areas, with few irrigation conditions, serious lack of nutrition and serious grass shortage. The soil management of chestnut orchard should focus on deep soil ploughing, scientific fertilization and ingenious use of herbicides to achieve annual high yield, stable yield, high quality and high efficiency.

1 soil deep ploughing

Most Chinese chestnuts in Yanshan are planted in mountainous areas, so soil and water conservation projects should be done first. It is best to dig a ditch with an excavator before planting, which is more than 1 meter deep and wide to fully meet the needs of chestnut root growth and development. Strive to achieve: "gentle slope terraced, steep slope basin, mountain ditch with dam, tree plate under the tree." Secondly, it is necessary to turn deeply and expand holes, and within 3 years after planting, the whole garden should be turned deep, the soil should be pressed green manure, the soil should be improved, the soil organic matter should be increased, and the soil should be "deep, fertilized and pleasantries". Weeding should also be carried out with a depth of 10 cm to 30 cm, shallower near the trunk and deeper away from the trunk to avoid root damage (figure 1).

Fig. 1 Deep ploughing of soil in chestnut garden

Fig. 1 Deep ploughing of soil in chestnut garden

(2) Scientific fertilization

2.1 misunderstanding of traditional fertilization

Many chestnut farmers do not apply chemical fertilizer to chestnut trees at all because they think that applying fertilizer to chestnut trees does not increase production obviously, which discourages the enthusiasm of fruit farmers to apply fertilizer.

2.1.1 the wrong application time of chemical fertilizer in the main producing areas of Yanshan chestnut in spring, coupled with the fact that most of the chestnut orchards have no irrigation conditions, and the technology misleads "chestnut fertilizer, the effect of application after rain", so the fertilization time can not catch up with the maximum nutrient demand of chestnut trees. Resulting in inconsistent supply and demand of fertilizer, out of joint with each other, can not give full play to the maximum benefit of fertilizer.

2.1.2 Chestnut farmers who choose unreasonable fertilizer generally only apply nitrogen fertilizer and use more urea or diammonium, resulting in nutrient imbalance and excess vegetative growth of chestnut trees. The fertilizer efficiency period of ordinary chemical fertilizer is generally 50-80 days. When the chemical fertilizer is applied to the ground, it decomposes quickly, and when the chestnut tree is not fully absorbed, it is fixed by the soil, and most of it is wasted with air evaporation and rain infiltration, which can only absorb about 15%. When it really comes to the critical period when chestnut trees need fertilizer in autumn, fertilizer supply is not available, resulting in late de-fertilization, so partial application of fertilizer does not have a significant effect on increasing production.

2.2 Fertilizer requirement Law and Fertilizer selection of Yanshan Chestnut

The main results are as follows: (1) the Yanshan chestnut orchard is mostly built in the gneiss mountain area, and the soil nutrients are characterized by "lack of nitrogen, phosphorus and potassium", which should be replenished in time.

(2) Chinese chestnut is sensitive to trace elements such as manganese, iron and boron, and it is easy to get sick when lacking.

(3) most of Yanshan chestnut orchard can not be irrigated, and fertilization has no effect during drought.

(4) the period from mid-late April (sprouting) to late June (chestnut male flower falling off) is the key period of flower and fruit setting of Chinese chestnut in Yanshan, and it is the period when Chinese chestnut needs the most fertilizer. 70% of chestnut fruit in mid-late July is the period of rapid expansion of chestnut fruit, which is the peak period of potassium fertilizer; base fertilizer should be applied in autumn to supplement nutrients after harvest of chestnut in September.

According to the above characteristics, the fertilization methods of high nitrogen in the early stage, high potassium compound fertilizer in the later stage and base fertilizer in autumn were found out. Chinese chestnut belongs to chlorine taboo crop, so sulfur-based type should be selected for potash fertilizer. The "potassium sulfate slow and controlled release compound fertilizer" which is the most suitable for chestnut is selected according to the law of fertilizer requirement of Chinese chestnut. The compound fertilizer contains nitrogen, phosphorus and potassium, as well as manganese, iron and boron, which are sensitive to Chinese chestnut. Slow and controlled release fertilizer is a breakthrough in chemical fertilizer production. The validity period of the fertilizer is increased from 50 to 80 days of ordinary chemical fertilizer to more than 150 days, and the fertilizer utilization rate is increased from 25% of ordinary chemical fertilizer to 45% of 50%. Potassium sulfate type slow and controlled release compound fertilizer is coated outside and does not melt immediately when it is applied to the ground. With the increase of temperature and soil moisture, the nutrient demand of the tree increases and the nutrient is released gradually, which is consistent with the fertilizer period of chestnut. More nitrogen fertilizer was released in the early stage and more phosphorus and potassium fertilizer was released in the later stage, which can meet the requirement of non-de-fertilization in the whole growing period of chestnut.

2.3 fertilization methods for Chinese chestnut

2.3.1 during the period of fertilization, we should seize the return period of freezing from early March to early April in spring, and fertilize Chinese chestnut in time while the soil moisture is good. Fertilizing during the return period and good soil moisture can decompose part of the chemical fertilizer to meet the needs of the germination period. There is a "planting rain" in the normal year around May Day, which can meet the maximum nutrient demand of chestnut trees. In the future, nutrients are slowly released to meet the needs of chestnut trees throughout the growing season. The application of slow and controlled release compound fertilizer year after year as required can increase the yield of Chinese chestnut by 50% and 100%. After the chestnut fruit is harvested in autumn, apply more organic fertilizer.

2.3.2 the amount of fertilizer application is according to the predicted yield of Chinese chestnut, the soil quality is poor on the hillside and around the mountain, and the yield is 3-5 kg of chestnut. 1 kg of potassium sulfate slow and controlled release compound fertilizer is applied. The soil is deeper and more fertile. The chestnut garden produces 7-10 kg chestnut and applies slow-controlled compound fertilizer 1 kg.

2.3.3 fertilization method: work in groups of two. Near the drip line outside the canopy, one person digs a pit 20 cm deep with a pointed shovel, picks up the soil with a spade, sprinkles the soil with chemical fertilizer, and then puts the soil back, digging a pit per square meter, fertilizing 100g and 150g per pit (figure 2).

Fig. 2 fertilization of Chinese chestnut in early spring

Fig. 2 fertilization of Chinese chestnut in early spring

3 weeding in chestnut orchard

Most of the Yanshan chestnut orchards grow in the mountains, with poor soil quality and low nutrient content, so there should be no grass shortage all the year round, avoid weeds competing for fertilizer and water, and create a good environment for chestnut growth. The effect of artificial weeding is the best, but manual weeding takes a lot of time and investment, so it is difficult to achieve no grass shortage throughout the year. Chemical weeding can be used in a large area of chestnut orchard, chemical weeding three times a year.

3.1 weeding periods and methods

The first time was in early June. There was a "farming rain" around May Day in Yanshan area. after the rain, a number of weeds were unearthed one after another in spring, growing to six o'clock, with no more than five leaves, and the grass roots were still very small and easy to get rid of, and were closed with paraquat and corn fields. The weeds that come out have been removed, and the weeds that have not come out have been sealed, which has a very good effect, which can effectively prevent the exuberant growth of weeds in summer and avoid serious grass shortage.

The second time is from late July to early August, using paraquat plus 2mae 4m D butyl ester to get rid of summer weeds and keep the ground clean to facilitate the harvest of chestnut.

The third time is in early October. Get rid of all kinds of artemisia, bitter thistle and other overwintering weeds before winter, and choose paraquat with an effective content of more than 20% (mass fraction, the same after that) plus 2mae4murine D butyl ester. The weeds stained with herbicides can not return nutrients before winter, accumulate insufficient nutrients, can not survive the winter normally, and even the roots are frozen to death, which is a good prescription for the combination of chemical weeding and phenological weeding, reducing the number of weeds in the following spring.

After chemical weeding three times in the whole year, it can save labor, medicine and labor, and there can be no grass shortage all the year round. After three consecutive years of such management, there are basically no weeds and can effectively control the harm of weeds (figure 3).

Fig. 3 weeding in chestnut garden

Fig. 3 weeding in chestnut garden

3.2 elimination and treatment of the roots of Jingke and Ziziphus jujuba

Chestnut orchards are mostly planted in mountainous areas, but it is difficult to get rid of Jingke and mountain jujube roots, and it is easy to regenerate. Jingke, mountain jujube is a small woody shrub, it is best not to dig Jingke, mountain jujube root method, one is not completely kill the grass, the other is to cause soil erosion. Want to eradicate the optional glyphosate plus 2min 4murd butyl ester at once.

(1) time: before and after the Beginning of Autumn (August 5) is the nutrient return period of Jingke and mountain jujube, once medication can be completely eradicated, there will never be any future trouble [Jishan Huayao].

(2) method: ① uses a nebulizer water (15kg) plus 10% glyphosate water agent 1kg, plus 2jing4Lok D butyl ester 3 bottle cap (10ml), plus a handful of detergent (effective). ② uses 77% powder glyphosate 2 bags plus 15 kg of water, plus 2 meme 4 murine D butyl ester 3 bottle caps (10 ml). Pay attention to the weather forecast when spraying to ensure that there is no rain within 8 hours and avoid dew time. And all Jingke, mountain jujube leaves are sprayed on both sides of the medicine. In this way, the drug can be used at one time and completely eradicated.