Consider the relative susceptibilities of the scion and rootstock to fire blight when establishing new orchards. There is considerable variation among apple cultivars (and pear cultivars) in susceptibility to fire blight, although none are immune. Some cultivar/rootstock combinations are so susceptible to fire blight that investments in these combinations are extremely high risk. In the eastern United States, ‘Gala’ on M.26 is an example of a high-risk combination. For more information, read this article on Fire Blight of Apple.…
What is a dwarfing rootstock?
Apple seeds that are planted do not produce a replica of the type of fruit that was planted; therefore, trees must be propagated by vegetative means such as budding or grafting. Typically, they are grafted onto a rootstock, which is just another apple selected for certain characteristics, such as dwarfing and/or disease resistance. (But not eating quality!) The rootstock provides many benefits to the finished tree. The most important one is ultimate tree size control.
In apples, tree size has …
I have a small backyard and want to plant an apple tree. What should I plant?
Here are some factors to consider in selecting an apple tree for a backyard setting:
► How much space is available with full sunlight and well-drained soil.
Apple trees require full sunlight for optimal blossom initiation and development the summer prior to the actual crop as well as for optimal fruit quality during the fruit’s growing season. Shading from a home and adjacent trees and buildings will result in poor tree growth, fruit yield, fruit quality and possibly greater insect …
Do I have to stake all trees on all rootstocks?
No, you do not have to stake all trees. Generally, since we do not have commercialized dwarfing rootstocks for most stone fruits, these trees do not need to be staked. Apples are the primary tree fruit crop that needs to be staked, but not all rootstocks need to be staked; however, all trees benefit in their early life from staking to prevent wind whipping and leaning. The more size-controlling the rootstock, the greater the need to stake the tree. Trees …
Where do I purchase stakes for apple trees?
The tree stake desired and the number required will determine where you purchase your tree stakes. If using a conduit stake in a limited number, you can purchase from a local general hardware or do-it-yourself warehouse. For larger quantities of conduit, you can usually get a volume discount purchasing from an electrical supplier. Also, specialized metal tree stakes can be purchased and shipped as well. A Web search for “orchard tree stakes” will give you several to select from. However, …
For an apple tree, how many inches above the soil should I keep the graft union after planting?
For trees on size controlling rootstocks, the bud union should be 3 to 6 inches above the soil line. Remember that in some instances the tree can settle causing the bud union to become covered with soil. If the union is covered it may allow the scion to develop roots and the benefits of the size controlling rootstock could be lost. Conversely if the union is too high you may experience increased size control resulting in a smaller tree than …
What do apple rootstock leaves look like?
A general description of rootstock leaf characteristics does not exist, because each rootstock has leaves that are characteristic of that particular rootstock. Rootstock leaves, like cultivar leaves, can vary in size, shape, color, leaf margin serration, pubescence, petiole thickness, and petiole length. Also, they differ by the presence of stipules at the petiole base, and leaves may be flat or cupped. In general, the rootstock leaves will look different than the leaves on the scion cultivar, so one should be …
Will an apple tree grow differently if I plant the graft union high above the soil or close to the ground?
The planting depth is critical, especially for trees on dwarf or semi-dwarf rootstocks. When planting, dig the hole deep enough to allow the tree to be planted with the graft union 2 to 3 inches above the ground. If the tree is planted too deep and the graft union is below the ground level, the scion variety will form roots and the tree will become a standard-sized tree. Also, if the graft union is buried, the tree may send up …
Do trees planted on dwarfing rootstocks produce small apples?
Without question, a dwarfing rootstock can reduce vegetative growth, resulting in a tree with a smaller trunk, shorter height, narrower canopy, and lower root volume. These rootstocks, however, do not reduce size of leaves, flowers, or fruit. Nearly all NC-140 apple rootstock trials have evaluated rootstock effects on fruit size, and, in some cases, rootstock did in fact affect size. In no case was the relationship between the degree of dwarfing and fruit size such that the more dwarfing the …
What is apple scab, and how do I identify and manage the disease?
Apple scab is a fungus disease caused by Venturia inaequalis. It is of major economic importance and, if not controlled, the disease can cause extensive losses (70% or greater) where humid, cool weather occurs during the spring months. Losses result directly from fruit or pedicel infections or indirectly from repeated defoliation, which can reduce tree growth and yield. For more information, read this article on Apple Scab.
Answer provided by Alan R. Biggs, West Virginia University.…