This a fungal disease called cedar-apple rust. Cedar-apple rust is a common disease of apple and crabapple. The fungus that causes the disease, Gymnosporangium juniperi-virginianae, is unusual because it must spend a phase of its life cycle as a parasite on Juniperus species, such as red cedar or ornamental junipers. Control: Grow resistant apple or crabapple varieties. Apple varieties that normally show good to excellent resistance to cedar-apple rust include ‘Red Delicious’, ‘McIntosh’, ‘Arkansas Black’, ‘Winesap’, ‘Mollies Delicious’, ‘Spartan’, …
What are the disease-resistant apple cultivars recommended for Wisconsin?
The following are some of the cultivars that will grow well in Wisconsin:
• Redfree: This is an early season, medium-sized, attractive red apple. You can store these apples up to 30 days.
• Prima: Prima produces medium to large fruit, red blushed on yellow skin. Mild, juicy, white flesh matures a week before McIntosh. You can store this apple for one to two months.
• Priscilla: This is a medium to large apple if you thin trees adequately after …
I have a 'Gala' apple tree. Would planting a 'Granny Smith' tree in my yard serve as a pollinator for the other?
Yes, ‘Granny Smith” would be a good choice. If you can’t find a ‘Granny Smith’ tree, then a ‘Mollies Delicious’ would work well. To see a pollination chart for apple varieties, refer to this article on Pollination of Fruit Trees.…
Should I wait until after a frost to harvest my apples?
No, harvest apples before the temperature drops below about 28°F. That is canopy temperature and will not necessarily be reflected by the thermometer on your porch.…
I missed pruning a few dead branches in an apple tree. Can I remove them in the summer?
The best time to prune is early in the Spring before bud break. Dead or broken branches can be removed anytime, but keep other pruning to a minimum.…
What are some suggestions for growing apples successfully in Colorado?
Reliable varieties for this area are ‘Cox Orange’, ‘Red Delicious’, ‘Golden Delicious’, ‘McIntosh’, ‘Jonathan’, ‘Fameuse’, ‘Northwest Greening’, ‘Joyce’, ‘Wealthy’, ‘Lodi’, and ‘Haralson’. Select two different varieties for cross pollination and good fruit production. In most cases, planting semi-dwarf varieties rather than standard size trees will allow enough room for at least two different varieties in the landscape. For additional hints for growing apples successfully, see the Colorado PlantTalk script on Apples.…
What is the method to get apple trees to set fruit?
All varieties of apple trees require some cross-pollination for fruit set. Even though some varieties are listed as self-fruitful, they will set fruit more heavily and more regularly if they are cross-pollinated. For solid block plantings, select varieties such as spur-type ‘Winter Banana’, spur-type ‘Golden Delicious’, or flowering crabapples such as ‘Manchurian’ and ‘Snodrift’ for pollinizers. Place honeybees in apple orchards when the first blossoms open. For more information on managing fruit trees, see this article on Pollination of Tree …
I bought some Whitney crab apples for pickling. I ate one prior, and it was fine. After I did the pickling, I cut a few open and there was a brown ring around the core of the seeds. Do you know what might have caused this?
The brown flesh around the core may have been caused by a fungus such as Alternaria sp.that entered through the calyx early in the fruit’s development. The condition, called moldy core, often cannot be detected until the fruit is harvested and cut. Here is a note about moldy core from the University of Massachusetts Apple Team:
“Moldy Core: This disease causes a rot with visible fungal growth in the seed cavity and core of some apple cultivars, particularly Delicious …
What is the best way to tell when apples and pears are ripe?
Harvest time varies with individual tastes and locality. One may consider a fruit ripe, while another individual believes it is immature. However, fruit picked too soon does not store well and does not develop full flavor. Probably the most reliable index is the number of days after bloom: Red Delicious takes 135 to 155 days from full bloom to harvest, whereas Granny Smith takes 170 to 180 days from full bloom to harvest. Other factors to consider include seed maturity; …
How can I control insects and diseases on my apple tree?
Homeowners are often surprised at the damage pests can do to apples. It is not easy to grow apples as pretty as those seen in the grocery store. Several diseases and insects can damage apple trees. Besides spraying pesticides, other things can be done to reduce pest damage, but it is very difficult to grow quality apples without some kind of pesticide application schedule. Rake and destroy leaves in the fall to reduce damage from diseases that overwinter in infected …