Origin and Common Names
Acer negundo L. ssp. californicum (Torr. & Gray) Wesmael is a type of maple tree that is native to the western region of North America, particularly in California. It is commonly referred to as California box elder, California maple, and box elder maple.
Uses
The California box elder tree has various uses, both practical and ornamental. Historically, its branches were used by Native American tribes for basket weaving. Its wood is also used for making furniture, flooring, and musical instruments. As an ornamental tree, it is often planted in gardens and along streets.
General Appearance
The California box elder tree typically grows to a height of 25-30 feet and a spread of 20-25 feet. It has a rounded or irregular crown with several slender branches. The leaves are composed of 3-5 leaflets that are toothed at the edges and have a light green color that gives way to yellow in the fall. The bark is gray-brown and becomes deeply furrowed over time. The tree produces winged fruits that are green in the summer and turn brown when mature.
Growth Conditions for Acer negundo L. ssp. californicum (Torr. & Gray) Wesmael
Acer negundo L. ssp. californicum (Torr. & Gray) Wesmael, commonly known as the California box elder, is a deciduous tree that is native to western North America. It can grow up to 60 feet tall with a spreading crown and grows best in riparian habitats, floodplains, and open woodlands. The following are the typical growth conditions necessary for the tree to thrive:
Light
The California box elder tree prefers full sunlight to partial shade. It can tolerate some shade, but it may not grow as vigorously or produce as much foliage. In areas with hot summers, the tree may require more shade to prevent leaf scorching.
Temperature
Acer negundo L. ssp. californicum is a hardy species that can withstand a wide range of temperatures. It thrives in USDA hardiness zones 7-10, which have average annual minimum temperatures of 0-30°F. The tree can also tolerate high temperatures, but it may require more water during hot spells to prevent water stress.
Soil Requirements
The California box elder tree can grow in a variety of soil types, including loam, sand, and clay. It prefers moist, well-drained soil, but it can tolerate short periods of flooding. The tree may struggle in excessively dry or compacted soil, however, as these conditions can limit root growth.
Cultivation
Acer negundo L. ssp. californicum (Torr. & Gray) Wesmael, commonly known as the California Boxelder, is a small deciduous tree that belongs to the Sapindaceae family. It is native to California and can grow up to 30 feet tall with a rounded crown. The California Boxelder can thrive in various soil types, including clay, loam, and sandy soils. However, it prefers moist soils and full sunlight to partial shade. When planting, ensure that the tree has enough room to grow and develop a healthy root system.
Watering Needs
The California Boxelder is somewhat drought tolerant, but it requires regular watering during its first few years of growth. When the tree is established, it can go for extended periods without supplemental irrigation. Deep watering is essential to encourage the growth of deep roots that can withstand drought and other environmental stresses. It is recommended to water the tree deeply once a week during the hot season or when the soil is dry.
Fertilization
The California Boxelder does not require extensive fertilization. However, to promote healthy growth, you can apply fertilizer during the spring or fall. A balanced fertilizer with equal portions of nitrogen, phosphorus, and potassium can be used. Apply the fertilizer according to the manufacturer's instructions and avoid over-fertilizing.
Pruning
To maintain the tree's shape and promote healthy growth, pruning is recommended. Pruning should happen during the dormant season when the tree has shed its leaves. Remove any damaged or dead branches first, then prune the remaining branches as desired. New growth will emerge in the spring, and you can continue to maintain the tree's shape through pruning.
Propagation of Acer negundo L. ssp. californicum
Acer negundo L. ssp. californicum, commonly known as California box elder, is a medium-sized, deciduous tree that is native to the southwestern United States. This tree can be propagated by seeds, cuttings, and grafting, and each method has its advantages and disadvantages.
Seed propagation
Seed propagation is the easiest method to propagate California box elder. The tree produces seeds in the fall, and they should be collected before they fall to the ground. The seeds should be cleaned to remove any debris, and then they can be stored over winter in a cool, dry place. In the spring, the seeds can be sown directly into the ground or in pots. The germination period for California box elder is typically 10-14 days, and the seedlings should be allowed to grow for 1-2 years before transplanting them to their permanent location.
Cutting propagation
Cutting propagation involves taking a stem cutting from the parent tree and rooting it. This method can be done at any time of year but is most effective in the spring or early summer. The cutting should be 4-6 inches in length and cut from the parent plant with a sharp, clean instrument. The cutting should then be dipped in rooting hormone and planted in a well-draining rooting medium. It should be kept moist and in a warm, humid environment until it roots, which can take up to six months.
Grafting propagation
Grafting propagation involves taking a scion from the desired California box elder tree and attaching it to a suitable rootstock. This method is typically used to propagate desirable traits from a mature tree, such as its size, disease resistance, or fruit production. The grafting should be done in the spring, and the tree should be kept moist and in a warm, humid environment until the graft takes, which can take several months.
Disease Management
Acer negundo L. ssp. californicum (Torr. & Gray) Wesmael is prone to numerous fungal diseases such as verticillium wilt, powdery mildew, and anthracnose.
Verticillium wilt is a soil-borne disease that causes leaves to wilt and turn yellow, and ultimately lead to the death of the plant. The best way to manage this disease is to practice good sanitation by avoiding planting Acer negundo in infected soil and removing any infected plants from the garden.
Powdery mildew appears as a white, powdery coating on the leaves and stems of the plant. This is a common fungal disease which spreads rapidly in high humidity environments. To control this disease, maintain a dry environment around the plant, and prune off any infected plant parts.
Anthracnose is another fungal disease that causes brown spots on leaves and stems, which eventually causes the leaves to die off. Avoid handling wet plants, and prune off any infected parts of the plant.
Pest Management
Insects are the most common pests that can harm Acer negundo L. ssp. californicum (Torr. & Gray) Wesmael.
Aphids are small, soft-bodied insects that suck plant sap, causing the leaves to wilt and turn yellow. To control their spread, blast the leaves with water to knock them off or treat the plant with insecticidal soap.
Leafhoppers are small insects that pierce the plant's leaves, leading to yellowing and discoloration of the leaves. Manage these pests by removing any weed hosts that they might use while attacking the plant.
Scale insects on Acer negundo result in yellow leaves and a sticky residue on the leaves and stems. Dilute rubbing alcohol with water, and spray the plant to remove the scales.
Caterpillars are another pest that can cause considerable damage by eating the leaves. Use Bacillus thuringiensis or neem oil to control caterpillar infestations.
