This highly feathered tree is perfect for establishing the tall spindle planting system.
The quality of the nursery tree planted in the orchard is considered an integral and important part of Dr. Bruce Barritt’s planting systems puzzle. Simply, the better the tree, the greater the success of the orchard. Tree quality is important since it influences early fruit production and the ability of an orchard to quickly pay back investment costs and increase the overall profitability of the orchard. Even nurseries acknowledge the value of better quality trees by charging more for them on a graduated scale based on tree size.
Many studies have shown that higher quality trees result in earlier cropping and that the importance of early cropping far outweighs the cost of the plant material. Our recommendations have always been to buy the best quality trees you can find to start an orchard. Although tree density and orchard investment have increased and tree cost has become a more significant factor in orchard establishment, it is even more important today to start with a quality tree.
Loosely defined, a "quality" fruit tree:
• has sufficient caliper and height
• has a healthy and fibrous rootsystem
• has a standard rootstock shank length that has been budded or grafted to create a straight shank without a severe bend between the root and the scion and
• is completely pest and disease free
Today, a quality nursery tree must also have a complete set of scaffold limbs at the proper height above the graft union. From a physiological standpoint, quality trees must have high levels of nutrient reserves. Among the reserves, carbohydrates and nitrogen are the most important, as they provide energy and building blocks for new growth before photosynthesis and root uptake of nitrogen can occur after planting.
Numerous studies have shown that larger caliper feathered trees grow more and produce greater yields in the early fruiting years than do smaller caliper trees. In recent tree quality studies in New York, Dr. Terence Robinson found that large-caliper trees with lateral feathers produced 15.9% more fruit than strong unbranched whips, 32.3% more than smaller caliper whips, and 43.3% more than "sleeping eye" trees in the first seven years. When these data were fitted to an economic model in which trees were planted at appropriate densities, all associated costs added, and mature yields for all tree types adjusted to 1000 bushels per acre at year 8 and beyond, the feathered trees were 14% more profitable using a net present value analysis after 20 years.
The more the better
Not all feathered trees are the same. The more feathers the better. Research has shown that trees with fewer than four feathers will only produce 61% of the early yield of those with 4 to 10 feathers per tree and only 48% of the yield of those with more than 11 feathers.
Most new orchards planted in New York are on the vertical axe and tall spindle systems with tree densities from 800 to 1,300 trees per acre depending on variety, rootstock, and soil. These higher-density systems depend on significant second- and third-year yields, making feathered trees vital to their economic success. The minimum nursery tree recommended for planting these systems is one with at least 4 to 6 usable branches that originate approximately 24 inches from the ground and are 8 to 15 inches long. However, we much prefer trees with 11 to 12 feathers. These feathers should be well spaced along the main trunk, and be one third to one half of the size of the leader at the insertion point. All side branches are best removed on trees with fewer than four feathers to better balance future growth among feathers. This delays fruiting, but there are no practical options.
The only exception to this recommendation is with the super spindle or V super spindle system (with more than 1,800 trees per acre), where trees are planted so close together that little lateral extension growth is needed to fill the space. The ideal tree for these systems is one with short fruitful dards. It is extremely difficult to control vigor when unbranched nursery trees with vegetative buds are used in this system. The high cost of trees can make these systems unprofitable at normal tree prices.
Despite all that is known about the influence of tree quality on the success of an orchard system, growers often accept trees of lower quality, thinking they are saving money. Growers who use smaller-caliper unfeathered trees will find that the carrying costs from this high investment will overwhelm returns and negate the benefits of the high tree density on profitability.
The great news is that the nursery industry has recently been highly responsive in providing the high quality trees that are appropriate for the newest planting systems.
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