What Kills the Roots of Pepper Trees?

Armillaria Root Rot

• The roots of the pepper tree (Schinus molle) can be killed by Armillaria root rot, an oak root fungus caused by the pathogen Armillaria mellea. The disease is also commonly referred to as shoestring rot and afflicts many broadleaf trees and conifers, including the California pepper tree. True to its name, the disease rots away the roots of the tree, preventing them from properly uptaking and distributing water and nutrition from the earth.

Armillaria Damage

• As the leaves of the pepper tree are deprived of water and energy, they begin to discolor, grow smaller in size and prematurely fall from the tree. The death of branches follows, while the roots and section of the trunk nearest to the ground die. Bunches of mushrooms develop near the base of the tree and shoestring-like structures grow from the surface of the soil near the roots. The disease is potentially lethal to the entire pepper tree

Cotton Root Rot

• Cotton root rot, also called Texas root rot, is a soil-borne fungus of the Phymatotrichopsis

  species. In addition to the California pepper, it infests many other types of trees. The first sign of this disease is a rapid wilting and death of the leaves, although the foliage remains hanging limply on the tree, giving it a "frazzled" look. As the roots of the tree die, fungal matter in the form of a mat of spores may develop on the surface of the earth, although this is only common if a high degree of moisture exists in the soil.

Management

• Cotton root rot progresses more quickly in warm weather and easily spreads to adjacent trees and plants through the soil. Hosts that are known to be susceptible to cotton root rot should not be planted in any area where the fungus has been known to exist. There is no test that will determine the presence of the pathogen in the earth. Chemical control is sometimes successful in managing cotton root rot -- but must be administered every one to two years.