The causative agent of the black knot fungus is Apiosporina morbosa. The fungal growth on trees is easily noticeable as the affected tree possesses galls or swollen black-out growths on their roots and stems.

At the end of this article, you’ll be able to understand if black knot fungus is harmful to humans and learn ways to prevent or get rid of it.

Is Black Knot Fungus Harmful To Humans?

No, Black knot fungus is not harmful to humans. 

There have been speculations that because black knot fungus is spread through pores during the spring period, coming in contact with the galls on the affected area is harmful but this is not true. 

Touching the Black Knot Fungus is not harmful to humans as people might think. Although, it can be very harmful to trees if not treated appropriately with immediate effect. 

Black knots are a very rich source of a complex polymer known as Melanin. This melanin secreted by the black knot is used in the determination of skin color and hair color and it has a major scientific role or use in providing protection from UV radiation that causes cancer. 

It is also important to note that black knot fungus can be harmful if eaten as opposed to just coming in contact with it – of course, who would want to eat a woody substance that looks appalling to the eye. But if eaten, it can be fatal to humans because it contains cyanide. 

Cyanide which is a very active and deadly poison starves and deprives the body cells of oxygen. This deprivation of oxygen to the cells affects the brain and heart specifically. So in other words, touching the black knot fungus or rot is not harmful but eating it is. 

How To Prevent Black Knot Fungus 

Preventing a fungal growth like the black knot fungus on trees is very possible but requires a determined effort of consistently monitoring the trees and checking out for any sign of tree disease. This helps to maintain healthy trees and put plant diseases in check.

There are a few things one could do to prevent the black knot fungus from growing on trees or plants

Properly watering and nourishing with fertilizers when necessary.  Tree inspection for gall growth or any sign of fungal diseaseCleaning and sanitizing farm tools especially if they have been used on an already infected plant. Use of fungicidesProperly dispose of fallen leaves or infected stems or branches 

How To Treat or Get Rid of The Black Knot Fungus

The best and easy approach to treat an infected plant with a black knot is pruning followed by applying fungicides. Pruning is the removal or the secession of plant parts that are harmful or potentially cause injury to the whole plant. 

If the infected part is not pruned out, the black knot will crack the wood and make it susceptible to fungi which eventually weaken and decay the whole tree. Pruning helps to promote the healthy growth of plants and removes infected, dead, or dying branches. 

While pruning a plant, it is important to cut at least four inches below the gall (affected area) in case the disease is not visible within those areas but is present. After the pruning work is done, ensure to sanitize and disinfect the tools used so the pores from the affected tree don’t pass on to another.

After removing the galls and branches of the affected areas, the next step to properly getting rid of the black knot is to apply fungicides. Fungicide treatment kills the growing fungus on young shoots and protects them from the black knot disease. 

For large trees, the conventional spraying equipment would not be enough to cover the whole part of the tree. So, a piece of high-pressure spraying equipment is required to get total coverage of the tree. 

Conclusion

Black knot fungus is not harmful to humans but only lethal to trees if measures are not taken to properly check them. The DIY method of pruning infected trees most times proved ineffective because of a lack of experience. 

I hope this article has been able to resolve your confusions about Black Knot fungus. So, when you notice a fungal growth or gall on a tree, be sure to seek professional help. 

1.  Can Black knot fungus kill your trees?

Yes, they can kill trees if the fungal growth is not properly checked and monitored 

2.  Is black knot fungus transmittable to humans?

No, the black fungus disease is only transmitted between plants through the pores of gall growth on the affected area.

3.  What are the symptoms to look out for in a plant affected by black knot pathogen?

A plant affected by black knot would have prominent galls, slant or bent branches as a result of the gall’s growth, wilting leaves which eventually turns brown and die off and finally a sticky liquid will be seen on the trunk of the affected tree.