12 TREE Roor DISEASES. 


cation stating that the roots of fruit trees which penetrated 
the places where the fungus appeared to reside became 
infected, the fungus penetrating the tree and ultimately 
killing it. This material was forwarded to Kew for investi- 
gation. Sterile mycelium alone was present, which appeared. 
to agree in every detail with that of Dematophora necatrix, 
and the fungus was provisionally referred to that species in a 
brief report published in the Yournal of the Royal Horticui- 
tural Society (XIX., Part I., 28). The following account will 
give an idea of the injury caused by this fungus, as observed 
by Mr. R. Allen Wight, of Auckland, New Zealand* :-— 
“* This fungus, in the mycelial stage, attacks a great variety of tree roots, amongst 
the most conspicuous of which are the apple, pear, peach, and all other common 
orchard trees. The whitethorn is also very subject to its attacks, as well as a great 
many 4ézes, and several of the native trees and plants. It also attacks the cabbage, 
the potato, docks, sorrel, fern, and in fact is almost omnivorous, which is a marke:! 
peculiarity. The only plants I have ever known to resist it are the resinous pines 
and roses ; the former suffer at first, and the leaves turn yellow, but they ultimately 
recover, and I never knew one to succumb, whereas the contrary is the case with ail 
other plants attacked.” 
‘“In hedges of whitethorn, where roses have been planted at intervals, the thorns 
are killed and the roses remain intact and quite uninjured. In an orchard it will 
appear in patches, killing the fern and sorrel, and spreading until it reaches a fruit 
tree ; it then attacks the bark round the stem just under the ground, which speedily 
rots, presenting the appearance of having been cooked, and has an offensive smell ; it 
then proceeds along the roots, and the tree soon shows withered leaves, which drop 
off, leaving it bare ; and by and by it falls over and lies on the ground. Its move- 
ments are uncertain ; sometimes a tree here and there dies ; sometimes a whole row, 
and very often acres are swept off. Many entire orchards of fine trees are killed in 
afew years. This fungus is never found in clay or other damp soils, but always in 
very friable lands. Professor Kirk, of Wellington, says it is Lycoperdoz gemmatum, 
Batsch., and that ‘‘tar water” is a certain cure. The last statement is assuredly an 
error, and I think the first is also. For a great many years I have endeavoured in 
vain to procure the fruit of this fungus, using all the means that suggested themselves 
to me, without any success. I have seen large quantities of the Z. geszmatum growing 
in orchards where there is no root fungus, and I have seena very great many orchards, 
and watched several closelyswhere hundreds of trees are attacked, and could never 
find the mycelium connected with the Lycoperdon. 
“* The pest is most plentiful on the skirts of the primeval forests and on fern lands 
adjoining where no cultivation has ever been resorted to. Whole crops of potatoes 
are destroyed on such lands, and on dry lands where native tree stumps remain it is 
very prevalent. My own opinton is thatit isa fungus native to, and probably peculiar 
to, New Zealand (in the North Island only). All my experiments with sulphur and 
lime have failed. Kerosine oil used in winter has alone been of any use, and that 
has been used pure in winter without killing the trees. The fungi of New Zealand 
are legion, and very destructive, but this is the worst, and particularly as it is confined 
to dry soils. Where Iam now writing 500 trees have been killed within the last 
two years, and all remedies tried have failed. The apple scab, the siot-hole fungus, 

* Journ. Mycol, Wol. v., p. 190- 
