Origin
Populus trichocarpa Torr. & Gray ex Hook. ssp. hastata (Dode) Dode p.p. is a subspecies of the black cottonwood or western balsam poplar. It is native to western North America, including Alaska, British Columbia, and parts of the western United States.
Common Names
This subspecies of Populus trichocarpa Torr. & Gray ex Hook. is commonly known as the hastate-leaved black cottonwood or lance-shaped three-lobed poplar.
Uses
The wood of this subspecies is used for construction and paper manufacturing due to its strength, durability, and ease of processing. The bark of the black cottonwood has also been used for traditional medicine by Indigenous peoples.
General Appearance
Populus trichocarpa Torr. & Gray ex Hook. ssp. hastata (Dode) Dode p.p. is a medium to large-sized deciduous tree that can reach heights of up to 60 meters. The leaves are large, ovate, and three-lobed, with a lanceolate shape. The bark is greyish-brown and features deep fissures and rough patches. The black cottonwood produces male and female catkins in early spring, which are followed by small, round capsules containing numerous seeds.
Light Requirements
Populus trichocarpa Torr. & Gray ex Hook. ssp. hastata (Dode) Dode p.p. requires full sun to partial shade for optimal growth. The plant grows best under conditions of bright and direct sunlight, but it can also tolerate some level of shade. However, insufficient light can lead to stunted growth and poor development of foliage.
Temperature Requirements
Populus trichocarpa Torr. & Gray ex Hook. ssp. hastata (Dode) Dode p.p. thrives in temperate climates. It prefers cool to cold temperatures throughout the year, with a mean annual temperature ranging from 2 to 14°C. The plant is tolerant of low winter temperatures, with a range of -40 to 10°C, and it can withstand occasional frosts. However, temperatures above 30°C can significantly reduce the growth and vitality of the plant.
Soil Requirements
Populus trichocarpa Torr. & Gray ex Hook. ssp. hastata (Dode) Dode p.p. prefers well-drained soils that are rich in organic matter. The plant grows best in moist, sandy or loamy soils with a pH range of 5.0 to 7.0. It is tolerant of a wide range of soil conditions, including acidic and alkaline soils, but it cannot grow in waterlogged or saline soils. The plant has a shallow root system, so it requires a consistent supply of water to maintain healthy growth.
Cultivation of Populus trichocarpa Torr. & Gray ex Hook. ssp. hastata (Dode) Dode p.p.
The cultivation of Populus trichocarpa Torr. & Gray ex Hook. ssp. hastata (Dode) Dode p.p. starts with selecting an appropriate site for planting. The ideal soil for this plant should be well-drained, moist, and rich in organic matter. The plant requires full sun exposure to thrive and grow optimally.
When planting, prepare the soil by adding organic matter, such as compost, to ensure fertility. Ensure the spacing is appropriate for the plants to grow to their maximum potential without competition. The ideal spacing should be about 8 to 10 feet between plants.
Watering needs of Populus trichocarpa Torr. & Gray ex Hook. ssp. hastata (Dode) Dode p.p.
The plant requires regular watering to ensure it grows well and produces healthy leaves and branches. Water the plant at least once a week, especially during its early growth stages when the roots are still developing. Ensure to water the base of the plant and avoid spraying the leaves to prevent disease infection. Mulching around the plant can also help maintain a healthy soil moisture level.
Fertilization of Populus trichocarpa Torr. & Gray ex Hook. ssp. hastata (Dode) Dode p.p.
Populus trichocarpa Torr. & Gray ex Hook. ssp. hastata (Dode) Dode p.p. requires fertilization to supplement nutrients in the soil. Apply a balanced fertilizer during the growing period, usually in early spring before the first flush of growth. Avoid over-fertilization as it can lead to excessive growth and reduced disease resistance.
Pruning of Populus trichocarpa Torr. & Gray ex Hook. ssp. hastata (Dode) Dode p.p.
Pruning is essential in maintaining the shape and health of Populus trichocarpa Torr. & Gray ex Hook. ssp. hastata (Dode) Dode p.p. Prune the plant during the dormant season, usually in late winter or early spring before the onset of new growth. Remove all dead or damaged branches, and any suckers growing from the base of the plant. Avoid removing more than one-third of the plant's total height in a single pruning session.
Propagation methods of Populus trichocarpa Torr. & Gray ex Hook. ssp. hastata (Dode) Dode p.p.
Populus trichocarpa Torr. & Gray ex Hook. ssp. hastata (Dode) Dode p.p., commonly known as the black cottonwood, is a dioecious tree native to western North America. Propagation of this plant can be done through several methods:
Seed Propagation
Black cottonwood can be propagated from seeds. The seeds should be collected in the fall and stored in moist sand or sphagnum moss at a cool temperature. In the spring, the seeds can be sown in a well-drained seed bed. Scarification or stratification can help improve germination rates. Once the plants are established, they can be transplanted to their final location.
Cuttings Propagation
Cuttings can also be used to propagate black cottonwood. Hardwood cuttings collected during winter dormancy or softwood cuttings taken during summer can be used. The cuttings should be 15-20 cm long, with at least 2-3 buds. The leaves on the lower half of the cutting should be removed, and the remaining leaves should be cut in half to reduce transpiration. The cuttings should be planted in a well-drained rooting medium and kept moist. After rooting, the cuttings can be transplanted to a nursery bed.
Grafting Propagation
Grafting can also be used to propagate black cottonwood. Whip and tongue or cleft grafting methods can be used. The rootstocks can be grown from cuttings or seeds, and scions should be collected from selected trees of desired traits. The graft union should be wrapped tightly with grafting tape and covered with wax. The grafted plants should be kept in a humid environment until growth resumes.
Overall, propagation of Populus trichocarpa Torr. & Gray ex Hook. ssp. hastata (Dode) Dode p.p. can be done through seed, cuttings, or grafting methods. Careful selection of propagation materials and proper care can lead to successful establishment of this common tree.
Disease and Pest Management for Populus trichocarpa Torr. & Gray ex Hook. ssp. hastata (Dode) Dode p.p.
Populus trichocarpa Torr. & Gray ex Hook. ssp. hastata (Dode) Dode p.p., also known as black cottonwood, is a fast-growing tree species that is attractive to many pests and diseases. Here are some common pests and diseases that may affect this plant and ways to manage them:
Common Diseases
Cytospora Canker: This disease is caused by the fungi Cytospora chrysosperma. Symptoms include sunken cankers, yellowing and wilting of leaves, and dieback of branches. To manage this disease, prune affected branches at least 6 inches below the canker and dispose of them in a trash bag, removing them from the site. Do not prune during wet conditions or prune branches greater than 2 inches in diameter.
Sphaerulina Leaf Spot: This disease is also caused by a fungus, Sphaerulina musiva. It appears as small, yellowish-brown spots on leaves. To manage Sphaerulina Leaf Spot, the use of fungicides can be necessary. Avoid watering the leaves, prune to improve air circulation, and use resistant plant strains.
Common Pests
Poplar Borer: The Poplar Borer is a beetle that burrows into the bark of the tree, causing damage to the trunk. To manage Poplar Borers, use pheromone traps to capture adult beetles, prune out any infested branches, or utilize insecticides recommended for use against this pest.
Cottonwood Leaf Beetle: This beetle feeds on the leaves of black cottonwood trees. To manage Cottonwood Leaf Beetles, encourage natural predators such as birds or insect predators like ladybugs or lacewings. Use insecticidal soap or neem oil sprays to repel the beetles.
By implementing proper disease and pest management practices, Populus trichocarpa Torr. & Gray ex Hook. ssp. hastata (Dode) Dode p.p. can remain healthy and free from damage caused by pests and diseases.
