THE PLUM IN KANSAS. 13 



tree and then against another, and with two or three sudden jars fetches 

 all the insects off the boughs into the white umbrella, which gapes 

 widely open to receive them. Really, it is a most magnificent insti- 

 tution, but for its practical success three things are necessary: (1) 

 That the land should be decently clean, and not overgrown with rank 

 weeds four or five feet high. (2) That the orchard be a sufficiently 

 large one to pay the interest on the prime cost of the machine. (3) 

 That the tree have a clean trunk of some three or four feet." 



2. Gathering the fruit and destroying the larvae.. As the in- 

 flect, in its larva or grub form, is yet within the plums when they fall 

 prematurely from the tree, it is a very obvious mode of exterminating 

 the next year's brood to gather these falleti fruits daily and feed them 

 to swine, boil or otherwise destroy them. A simple and easy way of 

 •covering the difficulty, when there is a plum orchard or enclosure, is 

 that of turning in swine and fowls during the whole season when the 

 stung plums are dropping to the ground. The fruit, and the insects 

 ■contained in it, will thus be devoured together. This is an excellent 

 expedient for the farmer who bestows his time grudgingly on the cares 

 of the garden. 



THE KNOTS, OR BLACK GUM. 



In some parts of the country this is a most troublesome disease, 

 and it has, in neighborhoods where it has been suffered to take its 

 course, even destroyed the whole race of plum trees. The knots is a 

 disease attacking the bark and wood. The former at first becomes 

 swollen, afterward bursts, and finally assumes the appearance of large, 

 irregular, black lumps, with a hard, cracked, uneven surface, quite 

 dry within. The passage of the sap upwards becomes stopped by the 

 compression of the branch by the tumor, and finally the poison seems 

 to disseminate itself by the downward flow of the sap through the 

 whole trunk, breaking out in various parts of it. The sorts of plum 

 most attacked by this disease are those with purple fruit, and we have 

 never known the green- or yellow-fruited varieties infected until the 

 other sorts had first become filled with the knots. The common 

 Horse plum and Damson appear to be the first to fall a prey to it, and 

 it is more difficult to eradicate it from them than from most other 

 sorts. The common Morello cherry is also very often injured by the 

 same disease, and in some districts the sweet cherry also. There is 

 yet some doubt respecting the precise cause of these knotty excres- 

 cences, thou.gh there is every reason to think it is the work of an in- 

 sect. Professor Peck and Doctor Harris believe that they are caused 

 by the same curculio or plum-weevil that stings the fruit ; the second 

 brood of which, finding no fruit ready, choose the branches of this 

 tree and the cherry. This observation would seem to be confirmed 

 by the fact that the grubs or larvae of the plum-weevil are frequently 



