Key Technical Points for Late-Stage Management of Mature Prickly Ash Orchards

I. Strengthen management during the flowering and fruiting stages

(1) Boron spraying at flowering: During the full-bloom stage of prickly ash, spray 1-2 times with a 0.3% borax solution, which can noticeably increase the fruit-setting rate.

(2) Use of prickly ash reddening agent: Applying a reddening agent can promote coloring of prickly ash and increase yield. 7-10 days before harvesting prickly ash, spray the trees 1-2 times with a 200-fold dilution of the reddening agent, so that the ripening period of prickly ash becomes relatively more concentrated, picking efficiency increases by an average of more than 2 times, the peel is bright in color, the peel yield rate increases by 3.3%, and the yield per plant increases by 23%.

(3) Timely harvesting: Due to the influence of traditional habits, prickly ash growers generally pick too early, starting in mid-July and finishing in early August, resulting in poor flavor and low yield of prickly ash. The generally optimal harvest period is from August 5 to 15, which can increase yield per plant by 20% compared with the traditional method.

II. Strengthen fertilizer and water management. Fertilizer and water management should mainly focus on the following 3 periods:

(1) First, after the flowers fade and the set fruit grows to the size of a mung bean, immediately apply phosphorus and potassium fertilizer as a top dressing, and apply it once about every 8 days for 2-3 consecutive applications. Choose early morning or late afternoon just after cloudy or rainy weather has cleared, and spray foliar fertilizers such as a 0.3% potassium dihydrogen phosphate and 0.2% urea aqueous solution on the leaves to improve prickly ash quality, increase per-unit yield, and stabilize and strengthen fruit development;

(2) Second, immediately after harvesting, pruning, and heading back of prickly ash (around August 20), apply a heavy dose of potassium sulfate compound fertilizer; (3) Third, before the Start of Winter (around November 20), carry out pinching, thinning of branches, pest control, and orchard cleaning, then apply "wintering fertilizer" rich in organic matter.

III. Integrated pest and disease control. The common pests and diseases affecting prickly ash production mainly include: woolly apple aphid, mulberry white scale, twospotted black velvet longhorn beetle, oval short-bearded mite, cicada, prickly ash brown spot disease, rust disease, dry rot, etc. The year-round control of prickly ash pests and diseases is mainly carried out in 6 stages:

(1) Dormant period of prickly ash (December to February of the following year): Mainly clean the prickly ash orchard, prune diseased and pest-infested branches, and destroy them in a centralized manner. Remove various overwintering pests and diseases.

(2) Before prickly ash bud break (early to mid-March): Spray 3-5 degrees Baume lime sulfur mixture 1-2 times, or spray an 80:100:1 machine-Fowler mixture, or spray 800-fold scalecide once. Mainly control overwintering pests and diseases such as woolly apple aphid, mulberry white scale, dry rot, brown spot disease, and rust disease.

(3) After prickly ash flowers fall (late April to early May): Spray 800-fold carbendazim plus 1200-fold 45% phoxim emulsifiable concentrate, mixing just before use; if the disease is severe, spray 2 more times after one week. Mainly control pests and diseases such as woolly apple aphid, brown spot disease, and rust disease.

(4) Young fruit stage of prickly ash (April to June): Strengthen control of dry rot; lime sulfur mixture can be used to coat dry rot lesions once.

(5) From young fruit to mature fruit stage of prickly ash (June to August): Use 80% dichlorvos poison sticks to plug fresh frass holes of mulberry longhorn beetle and twospotted black velvet longhorn beetle. If rainfall during this period is 60-100 mm, spray 25% triadimefon wettable powder 600-800-fold solution once; if severe, spray 70% thiophanate-methyl 800-1000-fold solution once more after 10 days. Control pests and diseases such as mulberry longhorn beetle, brown spot disease, and rust disease.

(6) After prickly ash harvest (August to September): If rainfall during this period exceeds 60 mm, strengthen control of diseases such as rust disease and brown spot disease.