Experiences in the Improvement of Low-yield Trees for Myrica rubra

The low-yield trees of red bayberry mainly include: small old trees, prosperous trees, aging trees, low-yield trees in mixed forests and low-quality variety trees, etc., the reasons for their low yield are different, and should be reformed according to the actual situation.

1. Little old tree:

Because the amount of base fertilizer is small or even not, and the planting hole is small, the root system grows poorly, or because of the harm of diseases and insect pests and the climate influence of natural disasters, the tree growth is weak, the crown is small, and the branching ability is very poor. therefore, the number of flowering and fruiting is small, and the trees with this phenomenon are called small and old trees.

Specific transformation measures:

The main results are as follows: (1) Deep ploughing and widening planting holes, adding guest soil for transformation, applying more organic fertilizers to promote the formation of soil aggregate structure, so as to improve the ability of soil fertilizer and water conservation, promote the development of roots and branches, and form a tree crown as soon as possible. (2) moderately aggravate the short pruning of backbone branches, promote the germination of hidden buds of red bayberry, improve the structure of the crown, and apply appropriate amount of available nitrogen and potassium fertilizer to enhance the tree potential and make it bear fruit as soon as possible.

two。 Flourishing trees:

Due to the deep and fertile soil, or the partial application of nitrogen fertilizer in the soil, and then let it grow naturally, the vegetative growth is too prosperous, a large amount of tree nutrition is consumed on the growth of branches and leaves, the flower buds are difficult to form or few, and the tree enters the fruiting period late or the yield is very low.

Specific improvement measures: (1) controlling fertilizer and water, especially applying little or no nitrogen fertilizer, and appropriately increasing phosphorus and potassium fertilizer; (2) applying paclobutrazol in soil from October to November, applying 0.2-0.4 grams of paclobutrazol per square meter of crown projection area; or from March to April, the crown was sprayed with 700 mg / kg paclobutrazol; (3) in autumn, at the ditch depth of 30 cm near the crown drip line, appropriate amount of root cutting treatment And some large branches were treated with spiral ring cutting or upside-down peeling in order to promote the formation of flower buds and improve the yield and quality.

3. Aging trees:

Generally speaking, the economic life of red bayberry is 70-80 years, but due to improper management, or due to the influence of diseases and insect pests and natural disasters, trees with many withered branches, few leaves, bald inner chamber and little fruit are called senescent trees.

Specific transformation measures: (1) according to the specific situation of aging trees, local renewal. The trunk and main branches were truncated in batches for 2-3 years, leaving the strong branches in the middle and lower parts to erase too many sprouting tillers, so as to facilitate regeneration and rejuvenation. (2) at the same time of renewal, combined with the application of organic fertilizer, loosen topsoil and regenerated mud to promote the growth of new shoots and roots, and restore the crown and yield. (3) pay attention to cut off the big branches of the wound, and apply wax or tarmac to protect the wound to promote its early healing.

4. Low-yield trees in mixed forest: because the mixed trees around the bayberry tree are tall and too dense, which affects the ventilation and light transmission of the crown, resulting in low yield of bayberry.

The specific transformation measures are as follows: (1) the mixed trees should be thinned properly to improve the ventilation and light transmission conditions of bayberry trees. (2) if mixed with Phyllostachys pubescens, the bamboo whip must be removed because of its strong branching power.

5. Inferior variety tree: due to the poor fruit quality, although the yield is high, it is of little value, so it must be reformed by high grafting method.