VITALITY OF WEED SEEDS 



73 



Limit of Years during which 



Germinating Capacity was 



Retained. 



43 

 42 

 27 



26 



25 

 21 



18 



15 

 14 

 13 



12 

 10 



9 

 8 

 6 

 5 

 4 



Number of Species. 



i (Leguminosae). 



i (Leguminosae). 



7 (5 Leguminosae, 

 i Malvaceae, 

 i Tiliaceae). 



4 



4 



4 



i 



2 



I 



5 



2 



4 



2 

 70 



3 



3 



9 



97 



It is thus seen that the majority of seeds do not survive 

 for many years under ordinary conditions of storage, and that 

 eight and three years seem to be the critical periods for a 

 large number of plants. The actual periods of survival for 

 the wild plants and farm weeds tested in these experiments 

 may prove interesting : 



Latin Name. 

 (i) Ulex europczus 



(i) Convolvulus major 



(I) 



(2) 



(3) 

 (4) 

 (5) 

 (6) 

 (7) 

 (8) 

 (9) 

 (10) 



English Name. 



Gorse 



cynapium 

 Anagallis arvensis 

 Arctium lappa 

 Carum carvi 

 Daucus carota 

 Nepeta cataria 

 (Enanthe crocata 

 Rumex obtusifolius 

 Silene inflata 

 Vicia sativa 



Greater bindweed 



Fool's parsley 



Scarlet pimpernel 



Burdock 



Caraway 



Wild carrot 



Catmint 



Hemlock water-dropwort 



Broad-leaved dock 



Bladder campion 



Common vetch . 



Number 



of 

 Years. 



15 



(1) Conium maiulatum 



(2) Valerlanella dentata 



Hemlock . 



Narrow- fruited corn salad 



(1) Bryonia dioica 



(2) Hypericum hirsutum 



(3) Plantago media 



(4) Tragopogon porrifolius 



(5) Valeriana officinalis 



(6) Verbasc^lnl thapsus 



White bryony . 

 Hairy St. John's wort 

 Hoary plantain . 

 Purple salsify 

 Common valerian 

 Great mullein 



