372 



throw up earth}' runs on Para trees. The Lacessitus merely eats 

 portions of the dead bark, but the Gestroi bores in and destroys the 

 tree. 



Detection. 



The (restroi can be distinguished from the Lacessitus by the 

 following peculiarities : — The nippers of the large soldier ants are 

 red, and a white milky fluid will exude from the front and top of the 

 head if pressed ; the soldier ant of Gestroi will always attack when 

 molested. 



Remedy to be Applied. 



When the runs of "Gestroi " ascend the tree, either partially or 

 entirely, encasing it with mud, the following method should be 

 adopted : — 



At the base of the tree where the collar touches the ground, 



remove with a broad straight pointed knife a portion of the mud 

 encasement. This will reveal several small tunnels. Insert the knife 

 into one of these, and by gently levering the earth away from the tree 

 the aperture is enlarged. When sufficiently widened to admit the 

 nozzle of the fume pump, gently insert it : press clay round nozzle to 

 prevent any escape of fumes. Pump fumes into the tunnel. Take 

 great care not to block the tunnel when widening the aperture, and 

 do not push the nozzle in too far. Where fumes escape stop the hole 

 with earth. When a field is being treated instruct the coolies not to 

 remove the mud encasements on the outside of the tree, as they reveal 

 the tunnels. The fumes used are those obtained from 9 parts of Ars- 

 enic Oxide to I powdered Sulphur on red hot charcoal. 



Pumping should be continued for 6 minutes. The nozzle of pump 

 should be occasionally withdrawn to ascertain whether pump is in 

 working order. 



The tree has also to be pumped into, this is done as follows: — 

 With an auger slightly larger than the pump nozzle, bore a hole in 

 the trunk of the tree to its centre at the collar; pump into this hole 

 for 6 minutes, or until the pump ceases to work from back pressure 

 of fumes; plug up all holes in tree or surrounding ground emitting 

 smoke; and, finally, when the tree and runs are full of smoke, plug 

 the bored hole in the tree with a well fitting sound wooden plug, 

 tarred. This plug must be driven into the tree level with the wood 

 (not bark). The ant runs are frequently 100 yards and more in length. 

 Open the runs in about three days and see if the operation has been 

 successful; if not, repeat. Thoroughly inspect all tree stumps and 

 logs for ants, and if any are found, carry out the same operations 

 as above. 



Temporary Preventive Measures. 



The eradication as above set out, i.e.. pumping, takes a 

 considerable time, and as there may be -many trees on the Estate 



