Experiments studying degrees of adherence ability to various surfaces were undertaken with presumably epizoochorous diaspores of 14 native and eight introduced species from southern California. A commonly available laboratory shaker was modified so as to provide a standard means for dislodging diaspores from surfaces. Diaspores were dropped onto a cloth-covered board and percentages of dislodged diaspores recorded after inversion and then after intervals of shaking. Three fabrics were used: a velvet with short pile, an artificial wood with short curly strands, and a furlike fabric with straight strands. Attachment to the velvet was nil for most species, showing that a lower threshold for strand length necessary to promote attachment exists. On the artificial wool, some species tended toward brief attachment, some toward prolonged attachment, and some were intermediate. Results with the furlike fabric were similar, but a difference could be seen in that diaspores with hooklike devices adhered better to the artificial wool; a few species (notably grasses with bristly awns) showed better adherence on the furlike fabric. Diaspores were also tested on natural animal surfaces (one feather and four fur samples). Natural substrates proved comparable to artificial counterparts. Distinctive categories of diaspores are evident, based upon diaspore morphology and adherence capability. Nature of surface proves more important than weight or size of the diaspore in promoting adherence.
Carlquist, S., & Pauly, Q. (2017). Experimental Studies on Epizoochorous Dispersal in Californian Plants. Aliso, 11(2), 167–177. https://doi.org/10.5642/aliso.19851102.06