NAPIER GRASS, A PASTURE AND FODDER CROP FOR HAWAII 3 
agronomic description by Piper (10, p. 21), and descriptions of the 
genus Pennisetum by Phillips (9, p. 167), and by Bews (1, p. 241). 
VARIETIES OF PENNISETUM PURPUREUM 
Besides the Napier variety, Bews (1, p. 334) describes a taller- 
growing type, known in Africa as elephant grass, which is typical of 
the tropical high-grass savannas of central Africa. Pentz (8, p. 8) 
mentions a variety called locally "Umfufu", which he says is only 
another strain of the same species, having narrower leaves and a taller 
growth. Possibly these two just described are one and the same 
variety. 
Two varieties have been introduced into Hawaii — Napier and 
Merker. Merker grass was introduced as a distinct species, but is 
recognized today as merely a different strain of Pennisetum purpureum. 
Both of these grasses are spoken of as elephant grass, although the 
term was formerly used principally for the Napier variety. 
DISTINGUISHING FEATURES OF THE NAPIER AND MERKER VARIETIES 
Napier grass is characterized by its wide, bright green leaves; its 
slightly decumbent growth in the early stages ; the reddish appearance 
of its stems, particularly in very early growth; and its thick, some- 
what soft stalks present until the plant approaches maturity. The 
growth rate of Napier grass is somewhat slower than that of Merker 
grass, and maturity comes considerably later. The Napier-grass 
plants tend to tiller more, however, and become more leafy, thus 
making up for slower growth. The total amount of dry matter pro- 
duced per year is usually equal to or greater than that produced by 
Merker grass. Napier grass blooms in the autumn and whiter and 
seldom at any other time during the year. It seems to set seed but 
rarely in Hawaii and has not been known to produce seed in the field 
to any extent. Figure 1 shows a typical growth of Napier grass about 
60 days old growing at the Hawaii Experiment Station. 
Merker grass has somewhat narrower leaves than Napier grass and 
appears to have a rather blue-green color. It has a slightly more 
upright growth in the early stages, less red pigment appearing in the 
stems, and finer and harder stalks as the plant approaches maturity. 
It has a very rapid growth rate and a quick recovery after cutting. 
Merker grass often begins to bloom 60 days after planting and has 
been known to reseed itself readily in the field. Blooming is more 
profuse than in Napier grass, particularly during the summer months. 
Its more favorable seeding habit is possibly of some agronomic impor- 
tance in propagation, although for forage purposes both of these 
grasses are propagated almost entirely by vegetative means. A typical 
growth of Merker grass, in which blooming has begun at an age of 
60 days, is shown in figure 2. 
In spite of the characteristic differences possessed by these two 
varieties, at times, particularly in old stands of grass, it becomes 
difficult to distinguish between them. If they are grown side by side, 
however, from seedling stage to maturity, it is usually easy to identify 
either. The more pronounced reddish color of the stems, observable 
in new plantings, is one of the most characteristic features of Napier 
grass. The semiprostrate early growth is also distinctive in tins 
variety. In the more mature stages the Napier grass is more leafy 
