Fall is a beautiful time for most trees, but it’s also the time of year when we see Apple Scab, Mildew, and Spruce Needle Cast diseases appear.
Your Ornamental Crabapple and Spruce trees may be showing signs of these common fungal diseases that negatively affect their long term health. Here’s what to be on the lookout for this fall, so you can be ready to treat for them in early spring when spraying is most effective:
Apple Scab and Mildew
In the case of Ornamental Crabapples, Apple Scab and Mildew are two fungal diseases that attack the foliage of the tree. If the leaves of your Crabapple tree are covered with brown spots (see photo above), and the leaves have been slowly dropping all summer long, then your trees are infected with Apple Scab. The signs for Mildew are a chalky covering on the leaves that would also cause early defoliation.
Spruce Needle Cast
With Spruce trees, Spruce Needle Cast is a fungus indicated by a reddish cast to the second and third year needles. Eventually these needles will turn brown and fall off, leaving the interior of the tree looking very woody (see photo above). Colorado Blue Spruce are particularly susceptible to Needle Cast, but it also infects White Spruce and Norway Spruce, as well as Fir trees.
Easily Treated, But Timing is Critical
The good news is that Apple Scab, Mildew and Spruce Needle Cast are easily treated. Two rounds of a fungicide spray applied early in the spring takes care of these diseases very effectively. However, timing is everything!
The first round needs to be applied during mid-May, after bud swell but before new leaves and needles form. If you miss this window, the second spray later in June will only slow these diseases and not eradicate them entirely.
Here’s what you should do NOW to protect your Ornamental Crabapple and Spruce trees:
- Go out in your yard and inspect your trees for the symptoms described above.
- If you’re not sure about what you see, take a picture of the suspected disease and email it to firstname.lastname@example.org. Our Staff Horticulturalist Warren Liken can make a diagnosis and determine if a site visit is in order.
- If it’s determined that your trees are infected with one of these fungal diseases, go ahead and schedule your 2-part spray treatments for early spring RIGHT NOW. That way you won’t forget about it and miss that important window before new leaves and needles are formed when the treatments are most effective at eradicating these diseases completely.
Crabapples and Spruces are two of the iconic trees that are featured in many beautiful landscapes throughout Mid-Michigan. While early spring is the time to treat them if needed, fall is the time to assess their overall health.
Let Reder Landscaping help you with this and all your landscaping needs. Contact Us Today!