REPORT OF THE STATE BOTANIST FOR 1 924 99 



A CONVENIENT EABORATORY PLANT PRESS^ 



BY 



II. S. JACKSON 



The drying- of plants is at best a laborious and uninteresting-, 

 tlioug-h very necessary, phase of the making of an herbarium and 

 in the preservation of plants for illustrative or class study purposes. 

 The old system of changing dryers has, in large part, given way in 

 recent years to more modern and timesaving methods. The intro- 

 duction of the use of- corrugated stravvboard between the dryers 

 and the utilization of some source of artificial heat for drying- the 

 plants has taken much of the drudgery from the old methods and 

 in general has resulted in a better quality of herbarium material. 



The writer has used a simple type of plant press during the 

 past 12 years which has proven very practical and satisfactory for 

 general laboratory purposes. On account of the simplicity of con- 

 struction and the low initial cost of this apparatus, it has seemed 

 desirable to furnish a description of it with specifications and illus- 

 trations for the benefit of those who may not have solved the 

 problem of drying plants to their satisfaction. 



The first press of the sort to be described was constructed in 

 1911 for use in the laboratories of the department of botany and 

 plant pathology at the Oregon Agriculture College. From one to 

 four of them have been in constant use there since that time both 

 for general laboratory purposes and for use in connection with 

 classes in taxonomic botany. The writer has also used since 191 5 

 presses of similar construction in the botanical department of the 

 Purdue Agricultural Experiment Station. A number of persons" 

 from other institutions who have seen these presses in use at one 

 or the other of these places have adopted a similar type. 



The apparatus consists essentially of a box with rack on which 

 the plant press rests, provided below with a source of heat (figure 2). 

 The box is 15 by 183^ inches, inside measurement, and is open at 



1 Reprinted -with minor changes from the Proceedings of the Indiana Acad- 

 emy of Science, 1920: 183-86. 1921. 



" Ricker, P. L. Directions for Collecting Plants. Bureau of Plant Industry, 

 U. S. 'Dep't of Agriculture Circ. 126 : 27-35. I9i3- 



^A plant press constructed according to the plans furnished by Doctor 

 Jackson was installed in the State Botanist's oflice early in 1921, and has proven 

 to be of great value not only as a timesaver, but also in its capacity for drying 

 larger quantities of plants than could be handled by the old method of 

 changing dryers every day. The specimens are uniformly better than those 

 secured by any other method of drying heretofore tested in this office. 



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