ROOT DEVELOPMENT OF CROP-PLANT ECADS. 133 



only 0.5 to 1 mm. in diameter, are densely clothed with hairs and a great net- 

 work of fine, well-branched rootlets. These are several inches in length, while 

 the tertiary branches are 1 or 2 inches long and very numerous. Some 

 lighter-colored roots were intermixed with the brown ones. These are younger, 

 shorter, and often less branched, and take on the darker color and other 

 typical root characters when more mature. Below 2 feet in the lighter colored 

 subsoil at the lowland station the roots were very much less abundant. In 

 fact, at a depth of 1.5 feet they began to thin out considerably, but were quite 

 abundant to the working depth at 2.7 feet, while some extended 1 to 2 feet 

 deeper. The working depth of the roots in the upper plats was 2.3 feet; the 

 soil was very well filled with roots to a depth of 2 feet, although, of course, they 

 were not so abundant as in the lower plats, where the stand was better. A 

 number were traced to a depth of over 3 feet and a few to the maximum depth 

 of 3.8 feet. Shepherd (1905) reports the roots of 3-year-old brome-grass at 

 the North Dakota Agricultural Experiment Station at Fargo to be about 

 4 feet long. 



Ten Eyck (1900), working at the same station, found brome-grass, planted 

 in the spring and examined July 18 of the following year, had reached a depth 

 of over 4 feet and formed a good sod. At two years of age the roots were 

 found to a depth of 5.5 feet, the whole soil to this depth being fully occupied 

 by its roots. Five-year-old brome-grass from a lower, more poorly drained 

 area had roots only about 4.5 feet in length. At Manhattan, Kansas (1904), 

 he found three-year-old brome-grass roots penetrating through 4.3 feet of soil 

 to the solid limestone rock below. 



Orchard grass (Dactylis glomerata). — This grass was not excavated until 

 July 10, when it had reached heights of 5 and 12 inches respectively in the 

 upper and lower plats. An excellent stand and good growth characterized 

 the grass in the lower area; that on the upland was much thinner, but of a 

 healthy appearance. Notwithstanding the great difference in above ground 

 development, the working depth of the roots at the two stations differed but 

 little. It was 2.3 feet for the lowland plants and 2.2 feet for the upland. In 

 the former area the maximum depth of root penetration was 3.1 feet, in the 

 latter about 2.8. 



On August 26 the roots of the orchard grass in the lower plats were again 

 examined. The surface soil was literally filled with a great mass of tan- 

 colored fibrous roots to a depth of nearly 2 feet, below which level they 

 became fewer in number, but were abundant to a depth of 3.2 feet. The roots 

 are tough and rather coarse. They are well furnished with laterals 1 to 3 

 inches or more in length, which are themselves branched to the second order. 

 The ultimate rootlets are very fine. In the deeper soils the branching was 

 rather largely confined to one plane in the crevices. Some of the delicate 

 roots reached a maximum depth of 4.4 feet. Orchard grass grows in tufts or 

 bunches and does not form a continuous sod. The plants in the upland 

 plats had developed so poorly that they were not further examined. 



Ten Eyck (1904) describes the roots of this grass excavated at Manhattan, 

 Kansas, and states that those of a two or three year old specimen reached a 

 depth practically the same as the extreme height of the grass, which was 3.5 

 feet. 



Meadow fescue (Festuca elatior). — The root development of this important 

 forage grass was first examined on June 13 in the lowland plats. The plants 

 had an average height of 8 inches. The working depth of the root was 1.5 feet, 

 although some extended to a maximum depth of 2.3 feet. The grass in the up- 

 land plats was of a very thin stand and grew so poorly that the roots were not 



