This is especially true in the southwestern half of the viewing area where the.

The leaf drop is likely due to anthracnose. Anthracnose is a common fungal disease of sycamore, ash, maple, oak, and other trees. Anthracnose is most severe in years with cool, wet spring weather. While anthracnose may cause extensive defoliation, it does not cause serious harm.

However, if your tree's leaves are wilting and falling off soon after they emerge in spring, this is a sign of trouble. Sycamore species such as American sycamore (Plantanus occidentalis) and. Jun 16, Entire leaves may be killed and then fall.

Keep trees well watered during drought sycamores are naturally a river bottom tree and need lots of water, and fertilize to maintain tree vigor.

These symptoms are very similar to those caused by late spring frost injury. This disease is favored by cool, wet weather (temperatures under 60 ° F during budbreak and the first few weeks of growth). A severely infected tree may be defoliated several times in a single season. May 03, (such as we’ve had in St. Louis this spring) coincide with the emergence of the young sycamore leaves.

Both emerging and larger leaves will wilt, turn brown and fall from the trees. Cankers (sunken spots) develop on twigs and branches, and in severe Estimated Reading Time: 2 mins. May 09, This is Sycamore Anthracnose disease. It occurs typically in spring foliation during a period of persistent, cool, wet weather where the foliage is often wet for a long period of time & temperatures fail to rise above the 50s for many days (with overnight lows in the 30s & 40s).

It is often mistaken for frost damage.