Methods of identifying grasses (fwd)

[Sayed_Ali_Mohamad]

---------- Forwarded message ----------
Date: Tue, 14 Nov 1995 11:29:28 GMT
From: Dr Ted Peat <SBS_WP at wye.ac.uk>
To: Sayed_Ali_Mohamad <pbs-sm at wye.ac.uk>
Subject: Re: Methods of identifying grasses (fwd)


 
> As I understand it, there are two methods of identifying grasses, by (1) 
> picture-booking, or (2) keying it out.
> 
> Picture-booking is looking through books for species whose appearance is close 
> to the unknown, and then comparing their characters to the unknown's to see if 
> their is a matchup.  (This is what I do.)
> 
> Keying out a grass is using the keying systems found in most books designed to 
> identify grasses or other varities of flora.
> 
> I am wondering if anyone uses keys.  

Certainly, many people will, but they are much easier to use 
when you are familiar with tyheir jargon and once you know the 
most common species.

An alternative to the formal, dichotomous key is a multi-access 
key. One version of this I have seen (for UK, vegetative 
grasses) uses punched cards which list alternative character 
states. From each set of 2 (or 3 or 4) cards, you choose the one 
that fits your specimen. Repeat this for as many characters as 
you like. Holes in the cards correspond with species that fit 
each charactetr state. Line up the cards. Any common, vacant 
holes shine through: these are candidtae species.

There is shortly becoming avaialble a computer-based version of 
this approach. The program, called GrassID, again restricted to 
UK species will be available through CLUES, University of Aberdeen, 
email clues at aberdeen.ac.uk or www 
http://www.clues.abdn.ac.uk:8080/


> Are professional agrostologists capable of examining a grass unknown to them 
> (assuming there is such a thing) and, without referencing any books, telling 
> which tribe or genus the unknown belongs to?

Of course: this is a prime requirement for a professional, and 
not difficult with experience

Ted Peat

 
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