128 RECOGNIZING AND CORRECTING DECLINING FOR.\GE 



that it may be reexamined at any time. The comparative 

 density of the chief indicator species — both the palatable and 

 the unpalatable ones — sh'ould be noted. The value of this work 

 is greatly enhanced by collecting and preserving for future refer- 

 ence the main indicator and forage species found on the plot. 

 Photographs showing the density and character of vegetation 

 are also highly valuable. 



Reliable Indicator Plants. — Plants as indicators of forage 

 conditions obviously are not the same everywhere. As a rule, 

 however, the same genera will be represented, but the species 

 may be different. Reliable indicators of the various stages of 

 overgrazing in any region may be determined by observing the 

 plants that predominate on and about bed grounds, on livestock 

 trails, and on areas in various stages of depletion. The follow- 

 ing list of plants characteristic of the four successional stages, 

 as developed by the writer in the investigation here summarized, 

 will serve more or less perfectly as a check list of indicator plants 

 elsewhere. The list is arranged according to the natural grass 

 or weed stages, and the lowest or more temporary ones are given 

 first, for it is these especially that must be kept in mind in judging 

 the condition of a pasture. 



First or early weed stage: 

 Most characteristic species — 



Douglas knotweed {Polygonum Douglasii). 



Goosefoot, or lamb's-quarters {Chenopodium album). 



Slender-leaved coUomia {Collomia linearis). 



Tansy mustard {Sophia incisa). 



Tarweed {Madia glomerata) . 



Tolmie's orthocarpus {Orthocarpus Tolmiei). 



Other species of the first weed stage — 

 Androsace {Androsace diffusa). 

 Gilia {Microsteris micrantha). 

 Knotweed {Polygonum aviculare). 

 Monolepis {Monolepis Nuttalliana). 

 Peppergrass {Lepidium ramosissimum). 



