Origin
Juglans microcarpa Berl. var. major (Torr.) L. Benson, also known as Texas black walnut, is a plant native to the south-central and southwestern regions of North America.
Common Names
In addition to Texas black walnut, this plant is also commonly referred to as little walnut, Texas walnut, and niggerhead walnut.
Uses
The nuts produced by Texas black walnut are edible and often used to make various food products, such as baked goods and confections. The wood of this plant is also highly valued for its strength and durability, making it a popular choice for construction and furniture-making.
General Appearance
Texas black walnut is a deciduous tree that can grow up to 50 feet in height. Its leaves are pinnately compound and can range in size from 8 to 12 inches long. The tree produces small, round nuts that are enclosed in a thick, woody shell. Its bark is dark and furrowed, and its wood ranges in color from a pale yellow to a dark brown.
Growth Conditions for Juglans microcarpa Berl. var. major (Torr.) L. Benson
Juglans microcarpa Berl. var. major (Torr.) L. Benson, commonly known as the little walnut, is a deciduous tree that is native to the Southwestern region of the United States. The tree typically grows up to 60 feet tall and has a spread of 50 feet. In order for the tree to flourish, it requires specific growth conditions, which are discussed below.
Light
The little walnut requires full sun or partial shade in order to grow properly. It is essential to plant the tree in an area that receives at least six hours of direct sunlight per day. Since the tree prefers a slightly acidic soil, it is important to plant it in open areas where the soil is not overly alkaline, which can reduce its growth potential.
Temperature
Juglans microcarpa Berl. var. major (Torr.) L. Benson is a highly adaptable tree that can grow in a wide range of temperatures. However, it prefers moderate temperatures between 60 and 80 degrees Fahrenheit. The tree can tolerate extreme temperatures as low as -10 degrees Fahrenheit, but it may experience some damage if the temperature drops below this point for extended periods of time.
Soil Requirements
The little walnut prefers well-drained soils that are slightly acidic. The tree can tolerate a variety of soil types, including sandy, loamy, or clay soils. It is important to ensure that the soil is not overly alkaline, which can result in stunted growth or leaf discoloration. To improve the soil's fertility, it is recommended to mix organic matter, such as compost, into the soil before planting. The tree also benefits from regular fertilization, especially during the growing season, which can help promote healthy growth and fruit production.
Cultivation methods
Juglans microcarpa Berl. var. major (Torr.) L. Benson, commonly known as Texas black walnut, grows best in hardiness zones 6-9. It is advisable to plant the saplings in fall so that they can establish their roots during the colder months. The soil should be well-drained and should have a pH level of 6.0 to 7.5. Avoid planting in compacted soils or areas with salt accumulation.
Ensure proper spacing between the saplings at planting, as these trees need ample space to grow and spread. The recommended spacing is 40-50 feet between each tree.
Watering needs
Texas black walnut needs adequate watering to attain healthy growth and production. Young trees require more frequent watering than mature trees. Watering should be done once or twice a week to a depth of 2-3 feet for the first year after planting. Afterwards, the frequency and depth of watering can be reduced to once every two weeks.
During summer, watering frequency should be increased if the area experiences prolonged periods of drought or intense heat. Mulching around the base of the tree can help conserve moisture and decrease the need for frequent watering.
Fertilization
Applying fertilizer to Texas black walnuts is essential for maintaining healthy growth and production. The best time to fertilize the tree is during early spring before new growth appears.
A nitrogen-rich fertilizer is recommended, with a ratio of 10-8-6. Apply one pound of fertilizer per inch of trunk diameter. However, do not overfertilize as it can result in excessive growth, affecting the overall health of the tree.
Pruning
Pruning is necessary for maintaining the overall health and productivity of the Texas black walnut. Prune young trees to establish a central leader and strong branch structure.
The best time to prune is during winter when the tree is dormant. Remove any diseased, damaged, or crossing branches to prevent them from hindering the tree's growth or causing further damage.
For mature trees, prune every year or two to remove any dead wood or diseased branches. Remove any branches growing vertically and any that interfere with other branches. Proper pruning can also enhance light penetration and air circulation within the canopy of the tree, promoting healthy growth and fruit production.
Propagation of Juglans microcarpa Berl. var. major (Torr.) L. Benson
Juglans microcarpa Berl. var. major (Torr.) L. Benson, commonly known as the Texas black walnut, is propagated through seeds and grafting.
Propagation through seeds
Propagation through seeds is the most common method for Juglans microcarpa Berl. var. major (Torr.) L. Benson. The seeds should be collected from ripe black walnuts in the fall, and then soaked in water for 24 hours before planting. The seeds should be planted in a well-draining soil mix and kept moist until germination occurs, which could take several weeks to a couple of months. Once the seed has germinated, it should be watered frequently but not overly saturated.
Propagation through grafting
Grafting is the other method by which Juglans microcarpa Berl. var. major (Torr.) L. Benson is propagated. The plant has a hardy root system, which makes it a strong rootstock for grafting. The scion wood can be taken from a mature Juglans microcarpa Berl. var. major (Torr.) L. Benson tree and grafted onto a rootstock. The ideal time for grafting is in early spring while the tree is still dormant. The newly grafted tree should be kept in a cool, moist environment until it has fully established.
Disease and Pest Management for Juglans microcarpa Berl. var. major (Torr.) L. Benson
Juglans microcarpa Berl. var. major (Torr.) L. Benson, commonly known as the Texas walnut or little walnut, is a deciduous tree that is native to the southern Great Plains. While this tree is hardy and tolerant of harsh conditions, it is still vulnerable to various diseases and pests that can impact its health and yield. In this section, we will discuss the most common diseases and pests that might affect this plant, and suggest ways to manage them.
Common Diseases
Phytophthora root rot: This soil-borne disease can cause wilting, root decay, and eventual death of the tree. To manage this disease, ensure good drainage and avoid overwatering. Plant resistant varieties if possible, and remove and destroy infected plants.
Walnut blight: This bacterial disease can infect leaves, catkins, and nutlets, causing blackening and death. To manage this disease, prune infected areas and dispose of any fallen debris. Apply copper-based fungicides during the dormant period to prevent infection.
Powdery mildew: This fungal disease can cause a white powdery growth on leaves and other green tissues. To manage this disease, remove and destroy infected leaves, and improve air circulation around the tree by pruning to avoid overcrowding.
Common Pests
Walnut caterpillars: These caterpillars can defoliate entire trees, reducing growth and yield. To manage this pest, monitor for eggs and larvae and remove them by hand. Apply Bacillus thuringiensis (Bt) or spinosad-based insecticides at early stages of infestation.
Walnut husk fly: This insect pest can destroy the nut crop by laying eggs on the husks, causing them to turn black and fall off prematurely. To manage this pest, apply insecticides at early stages of infestation and remove any infested nuts from the tree and surrounding soil.
Scale insects: These small, immobile insects can cause yellowing and stunted growth of leaves and stems. To manage this pest, prune and dispose of infested plant parts, and apply horticultural oils to control outbreaks.
In conclusion, proper disease and pest management is crucial to maintaining the health and productivity of Juglans microcarpa Berl. var. major (Torr.) L. Benson. By taking preventive measures and promptly treating any outbreaks, you can help ensure a successful crop and a thriving tree.
