Nowhere is the action busier than around native Quercus, or oak trees, a keystone genus teeming with more life than any other ...

Oak decline disease is not just limited to one particular species and has been observed in numerous different trees with the most severe outbreaks noted in red, pin, scarlet, white, and black oaks.

The "yellow" in these names comes from the tree's inner bark, which is yellowish in color. Black oak generally grows to about 80 feet tall, but like the willow oak, some can grow to be 100 feet tall.

The iconic Big Tree, a 1,000-plus,-year-old coastal live oak at Goose Island State park near Rockport, before the Hurricane Harvey. The tree, one of the largest coastal live oaks in Texas ...

A deadly new oak-tree disease can be prevented by pruning them in the dormant season ... but “there is usually a yellow halo between the brown and the green healthy leaf tissue,” she adds.

Oak galls, those small fuzzy yellow or brown balls on oak leaves and branches, may signify the health of your tree, Texas A&M AgriLife says. They are tiny, fuzzy, and yellow or brown in color.

According to the DNR, the best way to stop the spread of oak wilt is to avoid pruning your oak trees during the disease’s high-risk period, which is April 15 through July 15.