Oh, yeah, I think my dad said to use Diazenon in the yars, like around the RV 
adn in any sandy area where fleas multiply. So long as you don't have 
chickens or other ranging foraging fowl and don't pull up sprouted grasses 
from the yard to feed the birds. I believe diazenon is systemic in effect. I 
can't use it as I have chickens free ranging that would eat it. i also just 
bought baby guineas that are supposed to eventually eat fleas and ticks. The 
singer Billy Joel had guineas for this reason.
Again good luck.
Barbara
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