Tcnh. A: 9 



and the fact that dry or loose soils may fall off as the auj^er is 

 withdravm from the ground. Both soil tubes and soil auf^ers should 

 be obtained, however, in order to be able to obtain soil samples 

 from any type or condition of the soil to be encountered. One 

 source for soil sainple tubes and soil augers is the National Agri- 

 culture Supply Co.., Fort Atkinson, Wis. 



It is important that, whenever possible, the soil samples should be 

 taken from the rhizosphere of the plant. Soil sampling tubes or 

 augers can serve to do this very well when it is not desired or 

 possible to uproot an entire plant because of its special value or 

 large size. 



C. Sanple containers can be of various sorts, the only requirement 

 being that they are moisture resistant. The usual soil sample is 

 about one pint to one quart in size. Satisfactory containers 

 include: round ice- cream- type cartons; freezer-type boxes which 

 can be folded flat, a space-saving feature; moisture-resistant 

 lined paper ba5;;s; and plastic freezer- t^^De bags. This latter type 

 of container is ideal because of availability, low cost, durability, 

 and compactness when empty. 



Plant specimens must be kept from drying out before examinations. 

 Roots can be left in the soil ball or replaced in the soil which 

 had been knocked off for field checking of the roots. Plastic bags 

 are particularly useful for packing plants, as they can be slipped 

 over the roots and soil mass and tie! securely about the plant's 

 stem. 



All samples should be labeled when taken, and the use of vraterproof 

 pencils and heavy-stock paper is recommended. This is particularly 

 important, if there is to be an appreciable delay before processing 

 the sample, and in all cases, if the label is placed inside the con- 

 tainer. The moistiu'e from condensation which developes in the closed 

 contai.iers can quickly obliterate the pencil or ink writing and dis- 

 integrate ordinary papor. 



Samples, when prevented from drying out, can be kept for several 

 days before being examined. If periods of extended delay before 

 processing can be conducted are necessary, the samples, perhaps, are 

 best stored under refrigeration, although this evidently is not tnie 

 for all kindi of the nematodes. 



D. Miscellaneous. Another recommended item of field equipment is a 

 coarse brush whj ch is used to clean soil from sampling tools and 

 from the operator's shoes and pants cuffs. This is an important 

 safeguard when collecting eamplas in locations where the lilcelihood 

 of inadvertantly transporting and spreading a nematode oest must be 

 considered. Examples of this are: wliere an apparently new occur- 

 rence of a. nematode is being checked, where a quarantine is in 

 effect, and where there are separate planting sites which may not 

 have the same kinds of nematodes. 



