Why are the leaves on my crabapple tree turning yellow?

The answer is a fungal disease called apple scab. A fungus called Venturia inaequalis infects crabapple leaves early in the spring. Most people don’t notice the disease, though, until these infected leaves turn yellow and fall off the tree.


  1. Choose resistant varieties when possible.
  2. Rake under trees and destroy infected leaves to reduce the number of fungal spores available to start the disease cycle over again next spring.
  3. Water in the evening or early morning hours (avoid overhead irrigation) to give the leaves time to dry out before infection can occur.

Similarly, why do crabapple trees lose their leaves? A: The leaf drop is probably due to apple scab, a fungal disease caused by the fungus Venturia inaequalis. Cool, wet weather in spring favors apple scab development. Crabapple cultivars differ in their susceptibility to apple scab.

Likewise, people ask, what is eating the leaves on my crabapple tree?

Japanese beetles feed on the soft leaf tissue and leaf veins of crabapple and other fruit trees. They cause the most damage in early summer, giving leaves a chewed-up, lacy appearance. Otherwise, the beetles might stop to feed before entering the traps.

How long does a crabapple tree live?

40 years

What does Apple scab look like on leaves?

How to identify apple scab. Leaf spots are round, olive-green in color and up to ½-inch across. Spots are velvet-like with fringed borders. As they age, leaf spots turn dark brown to black, get bigger and grow together.

What’s wrong with my crabapple tree?

The fungus, Venturia inaequalis, known as apple scab, is a leaf spot disease that can cause serious leaf drop on susceptible crabapple trees. Scab-infected leaves from the previous season, left on the ground around the tree are the source of fungal spores that can infect the crabapple the next spring.

What do you spray crabapple trees with?

Apply a foliar spray of zinc sulfate and urea in the fall. This spray forces the tree to drop its leaves quickly and causes rapid decomposition of the leaf litter.

What is the best fungicide for apple scab?

The best fungicides available for scab control at this time of the early season are the broad-spectrum protectants: Captan and the EBDCs. It is likely too late for copper (see previous article, “An early-season copper application will help avoid feeling ‘the blues’ about diseases”).

Should I spray my apple trees?

Answer: The main objective in spraying apple trees is to prevent insect damage to the fruit. The most important period to spray apple trees is from petal drop until just prior to harvest. Several applications will need to be made during this period.

When Should I spray my crab apple tree?

Trees should be sprayed twice in early spring for proper prevention (when leaves first appear) and then three to four weeks later when the flowers have fallen off. The disease cannot be stopped once symptoms are observed in mid-summer. The treatment helps prevent spores from taking hold to the leaves.

When should crabapple trees be pruned?

When to Prune a Crabapple Tree The time for crabapple pruning is when the tree is dormant, but when the possibility of severely cold weather has passed. This means pruning should be done in late winter or early spring, depending on your local climate and temperatures.

How fast do crabapples grow?

It depends. Some crab apple trees grow faster than others. Ornamental varieties like Purple Prince (purple foliage) and Red Jewel are considered faster growing than others. Generally speaking, you can expect one of these trees to grow one-to-two feet per year.

Can Apple scab kill tree?

In years with moist and cool spring weather, infection can cause widespread defoliation. In spite of severe leaf drop, apple scab rarely kills a tree. If severe defoliation occurs for several years the tree could be weakened, making it vulnerable to other problems. Scab can cause cosmetic blemishes on the fruit.

Do you need two crabapple trees?

Pollination of Dolgo crab-apple trees It is self-fertile and does not need a pollination partner, but fruiting will usually be improved if there is a compatible partner of a different variety nearby. The following varieties will pollinate this crab-apple tree.

What is apple scab?

Apple scab is a disease of Malus trees, such as apple trees, caused by the ascomycete fungus Venturia inaequalis. The disease manifests as dull black or grey-brown lesions on the surface of tree leaves, buds or fruits.

Do all crabapple trees produce crabapples?

Most people choose crabapples for their smaller size and for the pretty white or pink flowers that they produce in spring. Of secondary consideration is the fruit on a crabapple tree, but most will produce them. By definition, a crabapple is two inches (5 cm.) or less in dimeter, while anything larger is just an apple.

Do apple trees drop their leaves?

All apple trees are deciduous, meaning they lose their leaves every year. The leaves usually turn yellow or brown right after the fruit matures and fall completely off the tree by the start of winter. The trees go into a dormant stage during winter, meaning that no new growth occurs during the cold season.