[17] DIRECTIONS FOR COLLECTING PLANTS — KNOWLTON. 



may be pressed. They may become somewhat distorted by this proc- 

 ess, but they will be less so than when kept entire, and the time re- 

 quired for drying them will be much less. 



Having arranged the plant or as many plants as the space on the 

 sheet will economically admit of, auotlier thin sheet is placed over it 

 and one or two driers placed on top. Upon this another thin paper is 

 spread, the plants arranged as before and covered with a thin paper, 

 and so on until the portfolio is exhausted or the pile becomes too un- 

 wieldy for convenient management. If the press is likely to become 

 very full it is a good plan to have two or three half-inch pine boards of 

 the same size as the press boards, which are occasionally inserted and 

 will help to even up the pile. The number of driers required for each 

 plant of course varies with the nature of the specimen. If it is large, 

 thick-stemmed, or succulent, as many as four or five driers may be re- 

 quired, but if a small, delicate annual one drier will be sufficient. 



The press being full or the number to be pressed having all been 

 arranged, the upper press-board is placed on the top of pile and the 

 l^ressure applied by means of the strap, 



" How hard to press plants is still an unsettled question, and bota- 

 nists differ widely upon it. My own experience has led me to make my 

 first pressure quite light. The easiest way to strap up a press full of 

 plants is to place them on the floor, with the knee upon the upper 

 board, draw up the strap, and buckle it. The buckle should be made to 

 come on the side from you, and be at first quite low down ; as it is drawn 

 it will rise, and should never be allowed to come up to the upper press- 

 board. 



" How long should plants remain in press *? Never over 24 hours for 

 che first time, and certain plants will suffer if left in so long. Much, 

 however, depends upon the pressure. Those who press their plants 

 hard must change them oftener. If the above suggestions are followed 

 it is best to change the driers at the end of 12 hours. The second 

 time they may, in most cases, be allowed to remain in 24 hours; 

 after this they should be changed every day for about 4 days. The 

 pressure may be slightly increased after each change, and after the 

 fourth day it is usually safe and advisable to leave them in the press 2 

 days, then change and leave in 2 days more under hard pressure, after 

 which they may be taken out, the driers renewed, and the package laid 

 aside for a week, with merely a board or a book upon it." (Ward.) 



The process of changing the driers is even more simple than that of 

 pressing. The press, filled with the plants to be changed, is placed 

 before you, on a table if possible, or on the ground, and the upper press- 

 board taken off and placed beside it. The pile of fresh driers is placed 

 by the side of the empty press- board, and one or two of the driers laid 

 upon it. The wet driers above the first thin papers are taken off and 

 the thin papers containing the plants are carefully removed to the new 

 pile. Fresh driers are placed on the plants and another plant in the 

 28323— Bull. 39, Pt. B 2 



