c % 
ones OE fi 2 
1 Noy., 1899.] QUEENSLAND AGRICULTURAL JO RNAL. \ f + 463 
; Bae ey . 
: SSCR OU 
lost. I should like to be able to say that a great argument-in 
avour of this 
way of dealing with the enemy is that the nut-grass cannot get a chance to 
ropagate itself by seed. Of course this is the case so far as it goes elsewhere, 
Dut I am compelled to admit that in this place I have never been able to raise a 
solitary nut-grass plant from seed, though I have tried hard to do so. Two or 
three years ago t offered a reward of 5s. to any of the employees here 
who would bring me a nut-grass seedling, or succeed in raising a single plant 
from seed, but the reward has never been claimed. Whenever the seed was 
sown, the only result was a crop of another Cyperus with minute seed which 
grows in company with the nut-grass. This is not, of course, a proof that nut- 
grass does not reproduce its kind from seeds. It has been repeatedly asserted 
that it does so, but of all the many millions of plants here I have neyer ‘seen a 
Pant reproduced from seed. There are many plants, as pointed out by 
rofessor Kerner in his magnificent work, “The Natural History of Plants,” 
which change their reproductive methods under conditions which favour the 
use of one method more than another. He supports this view by an immense 
range of illustrations (vol.'2, page 452), and there seems little reason to doubt 
that nut-grass, when it grows under conditions which favour its reproduction by 
the vegetative method, is a case in point. TI am anxious to get fertile seed of nut- 
grass ; and if some Queensland readers will kindly post some apparently sound 
seeds to me, I shall be glad to do myself the pleasure of posting a copy of 
“ Nicholls’ Tropical Agriculture’? (one of the best cultural handbooks in exist- 
ence) to the sender of thé seed which first germinates. J am also saving likely 
seeds here, and am again haying it tried under all conditions. 
On Plate II., an endeavour is made to illustrate some points about the 
nut-erass which will afford us hints in the campaign against it. Ata is shown 
a shoot which was nipped in the bud at the commencement of its career. It 
sent out, you will notice, before it was cut down, two shoots. Of these the one 
going towards the left was the most forward and appearing above ground. 
When the support was cut off at a, the growth of the shorter one was stopped, 
but the other (nearer to }) had formed roots and was peeping above ground ; so 
it went ahead, but after a time the rapid ‘ Ay 
very” nipped this also, and the 
Shoot at was left without a support from the base of operations. You will notice 
how puny it is compared with the two immediately preceding ones, If left alone, 
‘the centre tuber would try to get above ground again with atuft of leaves. The 
paralysing effects of this cutting off the sources of supply is seen in the specimens 
photographed at e fg and h. At i is shown a slice from the centre of a 
‘healthy nut which has not been interfered with. 
The greatest depth at which I have ever known hut-erass to grow beneath 
the surface of the soil is shown at figure c, Plate II. It extended for 12 inches 
‘beneath the surface, but was deposited in that position by the flood of 1893, 
which brought down from the upper reaches of the river a good deal of nut-grass 
in the soil and deposited it in hollows and on the banks of the river. The 
nut-grass in this case grew vertically, forming a chain of nuts until it reached 
the light, when the underground shoots began to spread horizontally a few 
‘inches beneath the ground, as is its wont. The lower nuts were dead. The 
qualities which recommended the tubers to the Seythians for embalming purposes 
preserve the nuts for an almost indefinite time under ground, and it is one of 
the most difficult of all forms of vegetable life to kill. In lifting an asphalt 
walk here, which had been down for six years, a few tubers of nut-grass were 
found still alive under the very centre. Continued shade will Jall out nut-grass 
most effectually. The position on which the large shade garden here was built 
was one mass of the plant, but after a brief struggle it gave in, and there is 
now not a blade to be seen. Shade at a little height seems to be more effectual 
than the placing of any substance directly on the plant. When the shade is 
but light, the plant never makes any attempt whatever to flower, as if 
recognising the hopelessness of the task, but goes on propagating itself by 
‘tubers only, and when the shade is increased beyond a certain point it quickly 
dies out, though, as before said, the tubers retain their vitality for a long time, 
H1 
