Espalier is a technique of pruning and training apples in two dimensions, usually against a flat surface such as a wall or fence. The rootstock that you choose needs to induce enough vigor in the scion cultivar so that growth occurs but does not produce a tree with too much vigor. The environment where you are located will alter this decision. The colder, northern areas of the United States — that is, USDA hardiness zones 3 and 4 (look up …
What is fly speck, and how do I identify and manage the disease?
Fly speck and sooty blotch are surface blemish diseases caused by fungi that commonly appear together on apple or pear in late summer and fall. Although these diseases may shorten the storage life of fruit due to increased water loss, they do not cause decay, and losses are attributed to unacceptable appearance. During wet growing seasons, losses of 25% or more are commonly found even in orchards treated with fungicides. Many fungi are involved in this complex of pathogens, including …
How are finished apple trees produced in a nursery?
Here is a summary of a nursery production schedule for fruit trees:
• Late fall: Cut/dig rootstock liners.
• Early spring: Plant liners.
• Late summer: Bud rootstock liner.
• Early spring: Cut off top of rootstock liner above bud.
• Late fall: Dig finished trees.
• Early spring: Sell/ship finished trees.
See this article titled Nursery Production of Finished Apple Trees for more detailed information.
Answer provided by Robert Crassweller, Penn State University.…
Apple Root Suckers
Root suckers are apple tree sprouts that emerge from the rootstock. They grow around the base of the tree. The point of origin of the suckers is the root. This makes them distinguishable from water sprouts, which originate from aboveground parts of the tree. Root suckers cause problems for the main tree in three significant ways:
- They compete with the main tree for water and nutrients.
- They are a prime feeding site for woolly apple aphids.
- They are a potential
What apple cultivars are resistant or susceptible to quince rust?
Quince rust is a fungus disease caused by Gymnosporangium clavipes. The fungus infects fruit, but not leaves, of most apple cultivars. It infects both leaves and fruit of hawthorn. More information, complete with images and a table of cultivar resistance/susceptibility, can be found in this article, Quince Rust of Apple.
Answer provided by Alan R. Biggs, West Virginia University.…
What is the best dwarfing apple rootstock for my area?
The best dwarfing rootstock for your area depends on your location, soil type, and what apple production system you wish to utilize. Your location determines likely cold hardiness, vigor, and disease issues. The soil type will influence tree vigor and ultimate tree size. Your apple production system determines whether you need a rootstock which will result in a free-standing tree and what size that tree needs to be, or whether the rootstock needs to be more dwarfing and will result …
What apple cultivars are resistant or susceptible to fire blight?
Fire blight is a destructive bacterial disease of apples and pears that kills blossoms, shoots, limbs, and, sometimes, entire trees. The disease is generally common throughout the United States wherever apples are grown. Outbreaks are typically very erratic, causing severe losses in some orchards in some years and little or no significant damage in others. This erratic occurrence is attributed to differences in the availability of overwintering inoculum, the specific requirements governing infection, variations in specific local weather conditions, and …
What apple cultivars are resistant or susceptible to powdery mildew?
Powdery mildew on apple is a fungus disease caused by Podosphaera leucotricha. It can be a persistent disease of susceptible apple cultivars wherever apples are grown. It is the only fungal apple disease that is capable of infecting without wetting from rain or dew. Mildew severity and the need for control measures are related to cultivar susceptibility and intended fruit market. More information, complete with images and tables of cultivar susceptibility and resistance, is available in this article on …
What apple cultivars are resistant to cedar-apple rust?
Cedar-apple rust is a fungus disease of apple and cedar and spends parts of its life cycle on each host. It is caused by Gymnosporangium juniperi-virginianae. The fungus can infect leaves and fruit of most cultivars in the eastern region. A notable exception is ‘Delicious’, which is nearly immune. Find more information and tables of resistant cultivars in this article on Cedar-Apple Rust.
Answer provided by Alan R. Biggs, West Virginia University.…
What apple cultivars are resistant or susceptible to bitter rot?
Bitter rot is a fungus disease that causes fruit rot during the summer and preharvest period. The bitter rot fungi are almost worldwide in distribution and cause an especially important disease in the southern areas of the United States. Outbreaks can occur rapidly, and losses can be severe, especially under prolonged warm, wet weather. Several host species can be affected. On peach and nectarine, the same fungus causes a disease known as anthracnose, and on grape it causes ripe rot. …