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STUDIES ON VENEZUELA GRASS—I
[Vol. XXI, Part I,
Sir Edward Morgan, an English physician is said to be the discoverer of this
grass in Caracas venezuela. Besides being a relishable cattle feed, the grass was
reported to possess many wonderful properties of its own, namely, repelling
mosquitoes, ticks, the big fierce bachacho ants, and even the tropical venomous
snakes. In India also the grass is believed by some to possess these wonderful
properties orginally attributed to it, but some interesting experiments conducted
in South India [1946] to test its mosquito repelling properties proved to be quite
contradictory. The external application of the aqueous extract of the grass also
did not give relief to fowls infested with mites.
The hairy variety of venezuela was used in these investigations. Except for a
faint smell of the green herbage no mosquito repelling properties were observed.
This is a perennial grass with stem having distinct nodes and internodes. It has
velvety soft leaf-blades with prominent leaf sheathes which cover almost the whole
space between two internodes and is a bit sticky to touch. The stems are filled
with spongy pith. In the early stages of growth the grass gives a bushy appearance
and if left uncut new rootlets and shoots develop from each node and it shows a
creeping tendency.
EXPERIMENTAL
Lay out of plots
The grass can be propagated both by seeds and cuttings. In the present case
the former method was adopted. The seeds for the purpose were imported from
upper Assam where the flowering season of the grass is in November. About 90
per cent of the seeds collected in December and January are said to germinate there,
the period of germination being 7 to 8 days. The seeds were sown in the
nursery plots of the Indian Veterinary Research Institute Farm, at Izatnagar in the
middle of April 1946 and they germinated within six days. The seed beds were
properly watered at frequent intervals till germination was complete. The seedlings
were transplanted when they were about six inches high and planted in parallel
rows of about two and a half feet apart in the experimental plots, which consisted
of two oblong plots of land each comprising of one twentieth of an acre. This was
done just before the onset of rains in the month of June. They were not given any
fertilizer treatment but irrigated from time to time and kept free from weeds.
During the early stages of growth the grass emitted a faint smell, characteristic
of the grass with the exuberance of a greasy substance. At the height of about
three feet the grass developed 'trailing habit' which gradually turned into a creeper
of about six to seven feet in length at the end of one year. The growth, as measured
by the increase in length of the grass, appeared to be controlled by factors like
temperature and rainfall, etc. The summer growth seemed to be confined mainly
to the stemmy portions of the plant with restricted leaf development.
Nature of soil and yield per acre
The soil was of poor sandy type, low in calcium and nitrogen with a slight acidic
reaction. Nevertheless, the grass appeared to thrive well without much care and
management yielding rather a fairly heavy crop. Three cuttings a year from plot
No. 1 yielded about nineteen tons of green herbage per acre per annum, whereas