Concolor fir becomes an attractive evergreen tree that functions as a privacy screen and windbreak for landscaping uses. Interestingly, this slow-growing plant is handily to cultivate in the garden as long as the area has proper conditions that resemble its wild habitat.
However, it is advisable to grow the white firs in groups. This pyramidal shaped tree often experiences winter burn. Therefore, you need to know more information about the species. Read on the following article to find out its characteristics and other problems that may occur while caring for Abies concolor.
Abies concolor Facts
This drought-tolerant tree can grow about 127 cm tall and 101 cm wide. It is the most adaptable fir that has a lifespan of over 350 years. The plant is native to the western United States and inhabits the Rocky Mountains, New Mexico, the coast range in California, and Oregon.
The beautiful mature plant has a crown that resembles a dome but forms pyramid-like foliage when still young. Although it can be a wind block, be aware of over-windy conditions in an exposed area. Thus, avoid growing a single tree in this kind of site.
Pendula, a weeping white fir, is one of the commercial cultivars that become a great plant due to its hardy wood, ornamental purpose, and easy-to-grow feature. However, it cannot be city foliage because concolor fir is prone to pollution.
White Fir Identification
Concolor fir features an elongated symmetrical-shaped tree with silvery blue-green needles. There are lovely drooping lower branches that touch the ground. The stems give citrusy fragrance while breaking. Although the shoots are not as sturdy as the spruces, they will not cause any damage.
An adult tree turns its shape into a round with many trunks. The white fir has flat and tender leaves, whereas the spruce needles look sharp and square.
The needles that locate on the top of the stems are 3.8 centimeters long. They grow from the branches by forming a curved shape.
Furthermore, the bark has a smooth surface with a gray hue. A color-changing happens from ashy-gray to dark gray-brown while getting mature. At maturity, it features deep irregular wrinkles and smoothened scales.
Then, the erect cones come in a cylindrical shape and bring yellow-green and purple colors. Their size is about 5 cm to 13 cm long.
However, concolor fir has inconspicuous flowers. The male pollen cones vary from red to red-purple, whereas the females come in rosy-red and locate at the top of the tree.
Growing Concolor Fir
Although concolor fir can withstand in any conditions, you need to know the best soil preferences to grow this shade-tolerant tree. Do not choose a location with heavy clay and wetlands. Opting for a place that is close to over-irrigated land is not recommended.
If you have a clay-based site, it will cause a problem. Therefore, add lots of compost and organic matter to provide proper drainage. The tree appreciates other types of well-drained areas such as sand, loam, and acidic land.
You can propagate concolor fir by seeds or stem cuttings. Cultivating from seedlings is an effective method because the tree produces an abundance of fruit grains. Get them by breaking the pine cone and spread over the planting area.
Meanwhile, propagation with stem cuttings seems to be more challenging. It is because the rooting needs a lot of time after being planted. The process takes about four months and needs plenty of organic substances to promote the growth of the new shoots.
You can start cultivating concolor fir in spring and summer. Add mulch on the surface to maintain weeds, keep the soil humid, and avoid an extreme degree of hotness. While young trees develop, apply a protective covering from pine needles. They can control the levels of dampish conditions.
To achieve the best growth, prepare deep and well-drained soils that get both full sun exposure and partial shade. However, it does not like being cultivated in containers, so choose a planting area or open grassland.
Moreover, add plant spacing of about 9 meters apart, but get closer if you grow the dwarf cultivars. Then, make a perfect combination with hemlock and cedar on cultivating concolor fir along with the landscape edgings. Those large evergreens establish a hedge for protection.
Fortunately, a white fir seldom suffers from any diseases. However, aphids and scales are usually disturbing. Use a dormant oil spray to kill them, so the new shoots in the spring season will be pest-free.
Young concolor fir requires regular watering, but the mature tree can resist drought. Then, apply mulch around the plant to increase the humidity levels of the soil. Since adults do not need any fertilization, give evergreen plan food as fertilizer to the new foliage.
Since the white fir does not need pruning, just trim the tree with shears to maintain the pyramidal shape. It is essential if you want to grow for ornamental foliage. Shearing the plant is also necessary to eliminate the mischievous branches.
Concolor Fir Varieties
The white fir has over 40 types that attract attention due to their blue color. Here are some examples of concolor fir varieties that give attractive landscape uses.
The blue cloak cultivar is another slow-growing evergreen tree with a weeping form. It comes with remarkable blue leaves.
Among all concolor fir cultivars, Candicans have the bluest appearance. The tree has an upright growth habit. Moreover, the needles feature powder blue color and big size.
Instead of drooping over the ground, this cultivar tends to appear like a wind-swept form. Compared to other varieties, its needle coloration is green rather than a blue hue.
Conica is a cultivar of concolor fir that has a narrow and erect formation. This slow-growing tree becomes the best choice for small landscapes.
The erect evergreen tree has a conical shape. Its growth rate is around 15 centimeters tall every year. The needles’ hue is green or yellow-green. In the winter season, there will be a color-changing into gold.
This upright white fir is dense with its dwarf size. The tree has blue and large needlelike leaves. In ten years, the cultivar only grows about 183 centimeters tall.
Concolor Fir Diseases
Among all evergreen trees, the white fir rarely experiences any health problems. However, it can suffer from some illnesses due to fungal infections. Delphinella shoot blight is one of the common diseases.
Another disease is needle miner. Instead of these following diseases, various pests and insects often attack the plant. For example, make a fence around the tree to keep the deer away. Then, use a repellent spray as needed.
Delphinella blight is one of the health problems that might occur to concolor fir. It makes needles and shoots turn brown. The symptoms are similar to the signs of frost damage. Delphinella abietis starts infecting the new growth in the spring season.
Due to the infection, the needles and shoots are drawing into wrinkles as a loss of humidity occurs. They also languish since the tree is still young. Many black fruiting bodies appear on the needle layer.
To solve this problem, remove the infected trees from the planting area. Besides, modify the soil conditions to give protection from any fungal infections.
Providing proper air drainage, plant spacing, and the right location is necessary to manage the disease. Furthermore, apply fungicide spray can be an effective way to control Delphinella blight.
White Fir Needle Miner
Epinotia meritana causes white fir needle miner that makes the needles bleached-yellow during the late spring and early fall season. The larvae that mine the leaves have a yellowish-green or cream color with black and brown heads. Their size is at a length of 8 millimeters.
The color turns dark brown or orange when they become pupae. They grow about 6 millimeters long. You can see them while jutting out from the mined needle hole. Meanwhile, the adult moths reach 11 millimeters with dusty gray coloration.
The life cycle of the moths occurs every year. In June or July, the moths start laying one egg on each needle. The hatching season happens in August or September. Young larvae will pass the winter season, whereas the feeding activity will start in spring.
One larva can damage several leaves. During the outbreak conditions, the insect population increases to construct a web in six needles. The remaining webbed needle will keep on the tree during summer.
A stage of becoming the pupa happens in June or July. The adult moths will come out after two weeks. Mating activity will occur in 3 days of emerging.
Moreover, the infections of the moths give some effects. Concolor fir will deprive of leaves for several years, and the death of branches and trees occurs. The foliage shows a silvery appearance.
Likewise, the same defoliation comes from other insects such as tussock moths and spruce budworms.
Finally, consider concolor fir if you want to grow evergreen foliage with an eye-catching color in your landscape. It becomes the most resistant tree to any soil conditions. Enjoy the attractive appearance with its delightful scent in an open meadow.