32 



FUMIGATION FOR THE CITRUS WHITE FLY. 



experience — obtained by measuring the first ten or fifteen trees 

 covered, both wdth the tape and by pacing, and comparing the 

 results. In pacing, the actual distance traveled will of course always 

 be greater than the circumference as measured by the tape. With a 

 little experience the proper allowance can be estimated mth sufficient 

 accuracy. 



For obtaining the distance over the top of the tented tree the author 

 has devised a plan which will so simplify the careful estimation of 

 dosage in conjunction \\4th tables such as the one presented in the 

 appendix that a far greater uniformity of results and important sav- 

 ing of materials A\all 

 ^ ^ ^ follow its adoption. 



This method consists 

 in marking the tent 

 as shown in figures 6 

 and 7 and in Plate 

 VII. The tent is first 

 thoroughly water- 

 shrunk, after which 

 from one to three en- 

 tire conspicuous lines 

 are painted length^ 

 wise of the tent for 

 the length of the 

 full-length strips, 

 and one line at right 

 angles to longitudi- 

 nal line or lines. 



For bell tents and 

 sheet tents up to 

 about 35 feet in di- 

 ameter, one line 

 running lengthwise 

 of the strips will be 

 sufficient, although 

 three are preferable. 

 For larger sheet tents three lines should always be made. The tent 

 may be water-shrunk, if not already so, by allowing it to become 

 wet with dew or other means, after which it should be thoroughly 

 dried in the sun. The entire tent, or at least the central section 

 of full-length strips, is spread flat on the ground, and the middle 

 strip with the proper location for a median line is located. This 

 line should be painted with a good quality of black paint '^ (flexible 

 paint preferable) about 2^ or 3 inches wide. If three lines are 



ABC 



FiG.6.— Diagram showing method of marking tonts to aid in obtaining 

 dimensions of inclosed space when covering tree: AA, BB, CC, par- 

 allel lines painted lengthwise with the strips of cloth from one ' ' end ' ' 

 of the tent to the other; DD, cross-line passing through center of 

 tent at right angles to other three. [Figures on lines AA, BB, and 

 CC represent the distances in feet from the line DD and figures on 

 DD represent distances from line BB. For the purposes of the dia- 

 gram these distances are not proportional to the size of the tent.] 

 (Original.) 



« Paints containing linseed oil should be avoided. 



