Barley Straw for Algae Control

The use of barley straw for algae control has received a lot
of publicity in recent years. It is now common to find small
barley bales being sold in nurseries and garden shops for use in
water gardens and small pools to control algae. The word-ofmouth
reports of success with this method have led many people
to suspect that barley might also control algae in ponds and
lakes. What has research so far told us about the potential for
barley to control algae in these larger bodies of water? And,
what does the Environmental Protection Agency (EPA) say
about using barley straw as an algicide? These topics will be
addressed in this publication.

http://www.btny.purdue.edu/pubs/APM/APM-1-W.pdf

I've tried almost straw and found that it is totally invalid. I guess
Some people report that it works - perhaps in a warmer climate. I put bags
It is in my pond here in Colorado and string algae is grown in the bag!