A pathogen is an infectious agent that latches onto a host and causes disease. Plant pathogens are varied, but more often than not they are some sort of fungus or bacteria. Fungi tend to be the most rampant plant pathogens. They are easily spread from one plant to the next and can cause widespread damage if left untended.

Disease Prevention

Diligent maintenance can usually keep plant pathogens in control. Fungi germinate and live best in shady, humid conditions. Dead leaves are the best place for fungi to gather all winter before germinating and spreading in the spring. Keeping fallen leaves to a minimum will help fight off fungi.

Minimizing the number of lower branches on a tree will also help to combat pathogens. Fungi grow best in cool, moist places. Lower limbs are often in the shade, where it's cool, and often are moist because they are not in the sun to dry out. Keeping these branches sparse and far apart can discourage the growth of pathogens.

If you're just starting to plant trees, you can start planning to prevent pathogens. Plant trees within a reasonable distance of each other. Tight clumps will create the cool, moist climate that fungi love.

Fighting Plant Pathogens

If you're still having plant pathogen problems, fungicides can help you combat the problem. Fungicides can help keep a normal fungus problem in check with regular treatments. It's important that treatments be ongoing since new pathogens can be blown into your plants every day by winds.