High concentrations of soil B are detrimental to crop productivity in
certain arid and semiarid regions of the western United States. Produc
tion of tall fescue on B-affected soils may be a viable strategy to re
duce and maintain soil B concentrations at nontoxic levels for most ag
ronomic crops. A 2-year field experiment was conducted to study B upta
ke in tall fescue (Festuca arundinacea) Schreb, cv. Au Triumph grown i
n soil containing potentially toxic levels of native soil B. The soil
B concentrations (water-extractable B greater than 5 mg B liter(-1)) d
id not affect the dry matter (DM) yield of tall fescue. Boron concentr
ations in shoot tissue for both years ranged from 88 to 121 mg B kg(-1
) DM, whereas in root tissue, concentrations ranged from 50 to 60 mg B
kg(-1) DM. For both years of the study, soil samples were taken at de
pth of 0-45 and 45-90 cm at the beginning and end of the designated gr
owing season and analyzed for water-extractable B. Summary data from a
ll cropped plots at the two soil depths indicated that the mean water-
extractable B concentrations were reduced by 35% after 2 years in the
tall fescue plots, whereas losses of extractable B from bare plots did
not exceed 13% for both years. Tall fescue apparently can be used as
a component in an overall strategy to lower extractable soil native B
levels in irrigated agriculture soils and potentially reduce leaching
of B into shallow ground water.