Physical Control
If your dogwood is showing signs of anthracnose, prune off any symptomatic areas, including shoots, epicormic sprouts, or leaves.
The same goes for any dead areas. Get rid of them immediately and prune down at least a foot beyond the dead area.
You have to make a decision about big cankers, since those growing on the main portion of the tree might not be removable without killing or seriously harming the tree.
Any leaves that fall either during the growing season or in the autumn should be raked up and disposed of as soon as possible.
Don’t put the leaves on your compost pile or use them as mulch anywhere in the garden.
Do your best to prevent damage to the tree. Damage can come in the form of holes from borers or it can be trimmers nicking the trunk.
Biological Control
You can harness the power of beneficial bacteria and fungi to try and slow the progression but you can’t ever actually cure the disease.
Bacillus subtilis is a beneficial bacteria that can help slow the spread of the disease because it pushes out the pathogen and also invades the body of the fungi, preventing growth and reproduction.
CEASE Biofungicide
You can find products like CEASE that contain Bacillus subtilis available at Arbico Organics.
https://www.arbico-organics.com/product/cease-bacillus-subtilis-biological-fungicide/?a=2017
B. amyloliquefaciens strain D747 is another beneficial bacterium that works similarly to B. subtilis.
Bonide makes a product called Revitalize that uses B. amyloliquefaciens to help slow the progress of diseases like dogwood anthracnose.
Bonide Revitalize
Pick up 32-ounce ready-to-use or 16-ounce concentrate at Arbico Organics.
There is also a bacteria known as Streptomyces lydicus WYEC 108.
It occurs naturally in the soil and can be used to fight the fungi that causes dogwood anthracnose.
Actinovate AG
Actinovate AG is a product that harnesses this beneficial bacteria. You can find it available at Arbico Organics.
None of these will stop the disease, but they can slow it, sometimes dramatically.
If you choose one of these products, combine it with one or two of the following fungicides for the best chance at controlling the disease.
Organic Fungicides
As with biological control, fungicides won’t reverse the course of the disease, but they can slow or stop its progression.
Your usual fungicides like Mancozeb and copper both offer a measure of control. Potassium bicarbonate or hydrogen peroxide can also be useful in the war against anthracnose.
You should try to use multiple different control methods and swap them up every few months. This is to prevent resistance to fungicides.
Thymol is often effective. Guarda contains this ingredient, which is derived from thyme plants.
Purchase two and a half gallons at Arbico Organics.
While I’ve never tried it myself, a neighbor told me that they had great success with a product that contained an extract from the dreaded giant knotweed (Reynoutria sachalinensis).
Giant knotweed is wreaking havoc across North America as an invasive weed that is pushing out native species. Luckily, we can put it to work in controlling dogwood anthracnose.
Regalia biofungicide contains this ingredient, which helps the dogwood develop its own resistance to the pathogen that causes anthracnose.
For that reason, you should use it preventatively or at the very first sign of infection, along with some biological control or other fungicides.
Regalia Biofungicide
You can find Regalia in a variety of sizes at Arbico Organics.
In the end, you might be able to stop the disease early enough that you can save your tree from certain death.