Regrowth Reduction in American Elm and Sycamore by Growth Regulator Injection1

Abstract

Water solutions of commercial formulations of growth regulators were pressure-injected into the trunks of topped American elm (Ulmus americana L.) trees in June to evaluate their ability to reduce sprout regrowth. Regrowth was significantly reduced by methyl 2-chloro-9-hydroxyfluorene-9-carboxylate (chlorflurenol), N-[4-methyl-3-[[(trifluoromethyl)sulfonyl]amino] = phenyl]acetamide (fluoridamid), l,2-dihydro-3,6-pyridazine-dione (maleic hydrazide), succinic acid,2,2-dimethylhydrazide (daminozide) and 2,3,5-triiodobenzoic acid (TIBA); α-cyclopropyl-α-(4-methoxypenyl)-5-pyrimidine = methanol (ancymidol) and (2-chloroethyl)trimethyl-ammonium chloride (chlormequat) were ineffective. Some undesirable effects on the tree and foliage were observed. Maleic hydrazide (MH) and daminozide (SADH) were selected for additional field tests at 3 concentration levels on topped American elm and American sycamore (Platanus occidentalis L.). Regrowth was significantly reduced and foliage condition was acceptable for the high concentration of SADH and the low concentration of MH. Successive measurements in both experiments showed that sprout regrowth was reduced by an amount equivalent to at least 1 year of growth during the first 2 seasons following treatment.

Metabolism and Distribution of 14C-Maleic Hydrazide and 14C-Daminozide Injected into Red Oak1

“…The results of this study agreed with those of others who have reported formatin of this complex (5,7,15). In field studies it has been reported that, with the passage of time, red oak and other tree species overcome the growth inhibitory response to application of MH (2,12). Our findings suggest that in red oak such a response may be due to detoxification of MH to form an ineffective glucoside complex.…”

“…During the past few years injection techniques have been used to introduce growth regulators into shade trees to retard their growth, particularly under power lines (2,3,12,14). Of the several chemicals tested, maleic hydrazide and daminozide have been successful for retardation of growth of shade trees (2,12). MH has been commercially used to prevent sprouting in tobacco, onions, potatoes, and to inhibit the turf and shade tree regrowth.…”

Advances in Tree Growth Control by Trunk Injection

“…The completed prototype equipment system is estimated to have a retail cost of less than $1500. The equipment and methods described in this report are expected to be used commercially within the next few years, particularly since results of field research have shown that trunk-injected chemicals can significantly reduce tree growth and sprout development in mature trees (Brown et al, 1977).…”

“…1974 Experiments. Commercial formulations of daminozide, ancymidol, chlormequat, chlorflurenol, TIBA (Regim-8), maleic hydrazide, and fluoridamid (Sustar 2-S) were evaluated on 135 American elm trees during 1974 (Brown et al, 1977). The trees were topped in early April, leaving a substantial number of limb stubs to accentuate sprouting.…”

“…1975 Experiments. The same formulations of daminozide and maleic hydrazide used in the 1974 treatments, but at three concentrations each, were injected in American elm and American sycamore during 1975 (Brown et al, 1977). The injection equipment used in 1975 was the same as that used in 1974.…”