A Complete Analysis of the Latest Propagation Methods for Lacebark Pine

Lacebark pine is a tree species endemic to China. It is a light-demanding species, tolerant of poor soils and relatively dry, cold climates. It grows well on cool, mild sites with deep, fertile, moisture-retentive calcareous soils and loess soils, and has extremely high cultivation value. Its propagation methods include seed propagation, cutting propagation, grafting propagation and others. Seed propagation is generally the most common. Let's take a look below at how lacebark pine is propagated!

Seed Propagation of Lacebark Pine

For seed propagation of lacebark pine, the seedling-raising site should preferably be a well-drained, flat, deep sandy loam soil. Sowing immediately after the ground thaws in early spring can reduce damping-off in pine seedlings. Because it is susceptible to waterlogging, high-bed sowing should be used. Water the bed thoroughly before sowing. About 1 kg of seed per 10 sq m can produce 1000 to 2000 seedlings. After broadcast sowing, cover with 1 to 1.5 cm of soil and put up a plastic film, which can increase the germination rate. Once the seedlings have emerged fully, gradually increase the ventilation time until the film is removed entirely. After sowing, the seedlings emerge carrying the seed shell, which drops off on its own after about 20 days; during this period, bird damage must be prevented. During the seedling stage, a shade frame should be set up to prevent sunscald, and before winter the seedlings should be earthed up for cold protection. Young seedlings have a long taproot and few lateral roots, so when transplanting, damage as few lateral roots as possible, otherwise they easily wither and die.

Cutting Propagation of Lacebark Pine

Rooting of softwood cuttings of lacebark pine requires both suitable moisture and suitable oxygen, so the cutting medium must have both good water retention and good aeration. Generally, vermiculite, quartz sand, river sand and peat are used as the cutting medium. Because rooting of cuttings requires oxygen, the shallower the better, generally 0.5 to 4 cm; for indoor cuttings, as long as the cuttings do not fall over, the shallower the better. Cutting length is generally 4 to 14 cm or more, and within this range they should have 2 to 4 internodes. Treating with an indoleacetic acid solution (concentration 0.005% to 0.01%) by soaking for 6 to 24 hours can increase the rooting rate of cuttings.

Grafting Propagation of Lacebark Pine

If lacebark pine is propagated by softwood grafting, the softwood should be grafted onto older Chinese pine rootstock. When grafted onto 3- to 4-year-old Chinese pine rootstock, the survival rate generally reaches 85% to 95%, and the compatibility is strong with fast growth. The scion should be selected from robustly growing new shoots, with a thickness of 0.5 cm being preferable. Before grafting, water the Chinese pine thoroughly once, so that with sufficient moisture the formation of callus tissue is favored. Winter grafting should be carried out in a greenhouse, and the temperature inside the greenhouse should be kept above 0°C. Below 0°C, wounds heal slowly and the survival rate is low. It can be carried out from November in winter to February of the following year, and after one month it can survive, with a survival rate reaching over 75%.