Sweetgum Blight as Related to Alluvial Soils of the Mississippi River Floodplain

Abstract

A BLIGHT OF UNKNOWN origin and cause has been very common throughout much of the range of sweetgum (Liquidambar styraci flua L.) since 1950. It is characterized by a gradual dying of the tree, often from the top down. The first visible indication is a thinning of a portion of the crown, caused when some buds fail to open and others produce only dwarfed, yellowish leaves. The ends of affected branches gradually die, often retaining the dead leaves for some time. Diseased branches may show up anywhere in the crown, but are most common in the upper part. Sometimes a tree with only a few branches visibly affected one year is dead the next, while in other trees the upper crown and leaders die back slowly, a branch or two a year. Occasionally the dying stops and the trees seem normal except for the dead, dried top . A cut into the wood of diseased branches often reveals tan or dark brown irregular streaks in the normally white sapwood. On diseased trees, a high percentage of the fine feeder roots are dead, although the larger roots appear healthy. The blight has been observed on a wide variety of sites, with damage apparently greatest in areas least suited for sweetgum. Some stands are completely ruined by it while others show little damage. Young, Toole, and Berry (1954), Hepting (1955), and Young (1955) have studied the progress and range of the disease, but of the investigators none has been able to determine the cause or discover a pathogenic agency. Although there are no detailed reports on the relation of soils to blight, the gross symptoms are similar to drought-induced dying and also have occurred in other species. The study reported here was undertaken to determine whether intensity of the blight on alluvial soils of the Mississippi River floodplain is related to soil differences.

Citation

Toole, E. Richard; Broadfoot, W. M. 1959. Sweetgum Blight as Related to Alluvial Soils of the Mississippi River Floodplain. Forest Science 5(1):2-9.