Casey Tree Farm Nursery personnel at Casey Tree Farm employ innovative planting techniques Nursery personnel at Casey Tree Farm have been hard at work the past few weeks, adding 2,000 trees — three acres’ worth — to the current nursery. Roughly 370 of the trees will be added using two innovative bare-root tree planting techniques — Missouri Gravel Bed (MGB) and root bags — that will limit the amount of stress on each tree during transplantation to future Community Tree Planting (CTP) sites in the Washington, D.C. area. Casey Trees mostly uses balled & burlapped (B&B) trees in its planting programs. At 2.5 to 3 inches in circumference, B&B trees weigh hundreds of pounds. Nursery Manager Brian Mayell believes these techniques will improve the tree stock Casey Trees receives for its planting programs. “Alternative growing techniques will allow us to produce trees with much lighter soil balls,” Mayell said, “which are better suited to the volunteer-based tree planting events Casey Trees coordinates.”
ROOT BAG
Using the Missouri Gravel Bed method, bare-root trees are planted in an irrigated gravel bed that can sustain them up to a year before being planted in a landscape.
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This spring’s CTP season included the first root bag trees Casey Trees has planted.
Nursery staff are using 14- and 16-inch root bags. Their weight at the time of transplantation will be significantly less than a B&B tree, ranging from 60 to 80 pounds. Lower weight could make it easier for Casey Trees to plant more trees at a single event or throughout a season. Bare-root trees are planted in felt-like bags filled with soil. As the tree’s roots reach the sides of the bags, they pinch and create nodules that hold valuable carbohydrates that will benefit the tree when it is transplanted. Smaller feeder roots subsequently grow from the nodules. Root bags differ from containerized trees — also light and easy to handle — in that containerized tree roots begin to circle, which is bad for the root system, when they come into contact with the plastic container. Root bags are easy to grow, transport and plant, which could reap benefits for Casey Trees’ tree planting programs.
Missouri Gravel Bed Created in 1985 at the University of Missouri, the MGB method entails dormant, bare-root trees planted in the spring in an irrigated planter box filled with gravel — the Farm’s is 30 by 30 feet and 16 inches deep. The trees are held for up to a year before being planted, in full leaf, in the landscape. Though not used as a proper growing technique, the MGB method makes handling the trees easier and less problematic because root growth in gravel
April 2012 | theleaflet