Tree Diseases Caused By Bacteria
Fire blight in flowerling crab. Arrow points to infected branch.
Canker on flowering crab apple. Bateria overwinter at the edge of the canker and ooze out in the spring.
Branch symtoms of fire blight showing curling of the branch tips and dead leaves.
Gall on roots of tree.
Large gall on main stem of tree.
Cross section through a gall on the main stem of a tree showing hypertrophy and hyperplasia of cells.
Cross section of an elm showing internal wetwood (brown region).