Weeds, weeds and more weeds

[ideasguy]

We learn here that this hardy plant is often grown as green manure or livestock fodder
http://en.wikipedia.org/wiki/Vicia_sativa

On my favourite Flora Of Northern Ireland site:
http://www.habitas.org.uk/flora/species.asp?item=14093
we learn that 

The forage plant (subsp. sativa) is very variable but is generally more robust than the native subsp. nigra: it is a tall trailing plant with pinnate leaves which have between 4 and 7 pairs of leaflets and terminal tendrils, and solitary or pairs of beautiful purple flowers, which are succeeded by peapod-type fruits 2 ins (5 cm) long. It is commonly encountered as a relic of cultivation or escape, in grassy places.
The native subsp. nigra is more slender, with very narrow leaflets and smaller flowers and pods. It grows in dry grassy places including sand dunes. Old British and Irish floras treat this as a separate species called Vicia angustifolia.

I think I may have the native subsp. nigra 

Here:
http://gallery.e2bn.org/image61693-.html
we learn that

it (Vicia sativa) can be distinguised from other vetchs as it has two black-blotched stipules at the base of the leaf. The seed pods have a long beak.

I note that the above sites dont say if it is Annual or Perennial.

This one does:
http://www.calflora.org/cgi-bin/species_query.cgi?where-calrecnum=8446
says:

Vicia sativa, a dicot, is an annual herb or vine that is not native to California; it was introduced from elsewhere and naturalized in the wild [Lum/Walker].

RE: (Eric H)

It has a mass of tiny white roots that seem to spread everywhere.

Thats what terrifies me!
I'm rather hoping its an annual, but like you, I'm not convinced.

[Trevor Ellis]

I've just put a question in the 'Books' section, trying to locate a book about weeds that I read about thirty years ago. Unfortunately, I haven't relocated the book as yet but it's content could well be interesting and useful to anyone with problems in that area and who tend towards organic solutions if I can locate it. If this sounds interesting, rather than me repeating, maybe check out the posting under 'Books'.

[ideasguy]

I hope you can locate it, Trevor.
If you do, you can post under Books and we can link to it from this topic.