Bur oaks are one of those trees. But no one wants to wait a lifetime to see it grow even to a decent height of 20 feet. Bur oaks have the largest acorns of all the native oaks according to the National Forest Service. This tree is easy to grow. It grows on dry uplands and sandy plains or fertile limestone soils and moist bottomlands. The bur oak wood is a hardwood and is marketed as white oak.
The bur oak's range is vast. It grows in the eastern United States and the Great Plains. It is the most drought resistant of all the North American oaks. After this summer's drought and heat, you need a tree that can endure. Bur oaks have been known to hybridize with nine other oak species. These are white, swamp white, gambel, overcup, swamp chestnut, chinkapin, English, post and live oak.
Littleleaf linden trees are moderately drought tolerant in comparison to bur oaks. The littleleaf linden can grow to about 60 feet high by 40 feet wide. They have a wide range of soil where they will grow well. Sandy soil, loam, clay, acidic, alkaline, well-drained and occasionally wet. Other than being susceptible to verticillium wilt, littleleaf lindens do not have any serious diseases.
Many trees are susceptible to verticillium wilt, particularly maples. Verticillium wilt can cause dieback of branches and death to the entire tree. This is a soil-borne fungus. Once inside the tree this fungus blocks the conductive tissue so that water cannot flow through the limb(s) and then wilts. The tree may have other symptoms beforehand such as slow growth, small yellow foliage, and scorching and heavy seed crops as chronic symptoms. Acute symptoms can be leaf curling, drying, red or yellow between the leaf veins, wilting and dieback.
Powdery mildew and anthracnose are leaf diseases and can be easily controlled. Powdery mildew is a white coating caused by a fungus on the leaf. Anthracnose is also a fungus which has a red-purple margin around a tan/brown area.
The American Sentry linden is a smaller size linden which can grow to 40 feet high and 25 feet wide with a narrow straight trunk. All lindens share in the characteristic where their limbs tend to droop or curve towards the ground, especially the lower limbs.
A lot of people favor the honeylocust. The most popular is the thornless honeylocust "Shademaster" which gets to a height of 50 feet with a width of 40'. People favor these types of trees because they are fast growing and want the shade to cover their yard quickly. However, there is a down side of a short-life span and weak limbs. Weak limbed trees do not withstand ice and snow storms or high winds. But despite this fact, the honeylocust has been used for windbreaks. And lucky for us with our alkaline soils, honeylocust do well in soils with a pH of 6.0 to 8.0. Honeylocust are also used for erosion control. This tree has become so widely used that it is used as a replacement for the American elm. Another better replacement for the American elm is Zelkova serrata; the Japanese Zelkova is also in the elm family and is rated as hardy in zone 5. I have seen only one of these in our area and it is growing in town in Burlington.
If you have lots of honeylocust and own a farm or ranch, your cattle and/or hogs may readily eat the fruits of honeylocust. The honeylocust is in the legume family and produces long bean pods at the end of the season. The beans in these pods contain about 12 to 13 percent protein. Other livestock will eat the young vegetative growth, according to the National Forest Service. There is a high competition for the fruits since gray squirrels, fox squirrels, white-tailed deer, bobwhite, starlings, crows and opossum feed on these fruits as well.
Other trees to consider are trees in the Plant Select[reg] Program. A smaller tree that does well in our area is a Russian hawthorn, Crataegus ambigua. This tree will be stay in the height range of 12 to 24 feet with a width of 6 to 12 feet. It requires moderate to xeric water. It will grow in soils that are sand, clay or loam. This tree has attractive bark, foliage and flowers. The fruit, which is eaten by birds, is a red fruit in the fall. The leaves have a golden color in fall.
The Seven-Son Flower, Heptacodium miconioides, is another small tree with a height ranging from 12 to 20 feet with a width of eight to 15 feet. The water requirement is moderate. The soil requirement is sandy or loam soil. The best attraction for this tree is the fragrant white flowers that bloom late in summer and then the persistent cherry-red sepals in the fall. This is a fast-growing tree. This is unusual member of the honeysuckle family which is very adaptable in a wide range of climates. This tree is not native, but collected at Hangzhou Botanical Garden during the 1980 Sino-American Expedition.
Lastly, another Plant Select[reg] tree, Clear Creek[reg] Golden Yellowhorn, Xanthoceras sorbifolium "Psgan," will grow to a height of 18 to 22 feet and a width of 10 to 15 feet. The water requirement is moderate to xeric. The soil requirement is garden loam, clay or sandy soil. This has white flowers with yellow centers that turn maroon. The leaves are ferny. The tree/shrub develops into a vase-shaped habit. This is especially hardy. This strain was developed at Green Acres Nursery in Golden. This is a fast-growing tree.
With the small selection of trees listed in this article, you can make a spectacular landscape. The more variation you add in your landscape, the better the chance will be to keep your landscape healthy and not be devastated when a host or disease comes along and wipes out the only variety of tree you planted, such as the elm.
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