An Improved Monolith Method for Excavating and Describing Roots

A root sampling frame was constructed to excavate roots in a soil monolith 152 by 41 by 91 cm in height. The frame and monolith were moved by farm hydraulic equipment. Access to the soil monolith was provided wtih a 10‐cm‐wide trench. The total proliferation attributable to four corn (Zea mays) plants was included in the sample, permitting more precise evaluation of horizontal and vertical root proliferation. Pin insertion into the monolith and later removal after washing, and before photography of submerged roots, permitted a better quality description of root proliferation. Corn root samples obtained 39 days after planting and application of three straw mulch treatments (about 31 days after emergence) revealed significantly different patterns of root proliferation horizontally and vertically. The relative difference of root growth was greater than that of the shoot, and shoot/root ratios varied from 1.3 to 3.1.