Parks : California Hypogaeous Fungi 



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ing intermingled and sometimes are difficult of determination. 

 The latter group forms a most important portion of the hypogaei. 

 They are often large fructifications and are frequently produced 

 in large numbers, and, above all, are strongly aromatic. These 

 aromatic species provide a large amount of food for the rodents, 

 the woodrats (Ncotoma) being especially active in the search for 

 them and leaving many signs of their work. The study of these 

 signs is of value to the truffle hunter. 



Many of the Tuberales appear to be without a conspicuous 

 mycelium, but the Hymenogastrales are usually associated with 

 an abundant white mycelial growth. The exposure of this my- 

 celium will often quickly lead to the desired plants. One or two 

 species of the Hymenogastrales are affected by parasites which 

 leave masses of golden spores under the leaves. The presence of 

 these spores serves as a guide to other species which are frequently 

 associated with the host plants. Excavations made by the rodents 

 for the different species, together with the many fragments left 

 among the leaves, serve as an additional guide. Sometimes on 

 warm, quiet days certain odors may be traced directly to certain 

 species. In the end, however, instinct and experience in selecting 

 favorable locations serve to secure the many different species, and 

 then very often the plants appear in unexpected places where ex- 

 perience shows they should not appear. 



Adjacent to San Jose there are ideally wooded hills of mixed 

 oaks both in dense forest and in open scattered groups, and in 

 other places not too far away there are fine forests of conifers and 

 other trees which give the greatest variety of country and timber 

 to work over. This district has been the scene of operations for 

 the last six years. And even when one knows the ground thor- 

 oughly it is surprising how little of it may be covered on a day of 

 good collecting. Frequently two or three hours will be spent in 

 working over the ground under a single large oak, and on several 

 occasions an entire afternoon has been spent in one place. The 

 collector may pass rapidly from one place to another, as experience 

 shows the ground to be barren, but though a place is barren one 

 day, it may within a week or so be producing an abundance of 

 fungi. 



