Is euryops pectinatus allelopathic?
 

Can anyone tell me if /euryops pectinatus/ (bush daisy)
is allelopathic, and if so, which other species are
most affected? I have a Stanley plum tree planted
close to some euryops, and here it is late April and
the tree has no leaves on it; a couple of flowers that
appear they won't set fruit. I planted the tree as a
bare root in January 2006, and it grew fine that first
year. I'm in Sunset climate zone 19, I think; can't
seem to get a precise fix on the zone from the zone
pages I can find on the map. Pasadena, CA if that helps.

Earlier, I had a comice pear (bare root) planted near
the same europs bushes, and that tree didn't do
anything for two years - no leaves in the spring,
although it would eventually put out a little bit of
foliage at the tail end of summer. I eventually moved
the pear tree across the garden to a different location
away from the euryops, and although it hasn't produced
any flowers or fruit (probably not enough chilling
hours), the tree does at least put out leaves and new
shoots in the spring, as I would expect it to do.

I have a Santa Rosa plum tree a little farther, but not
a lot, from the euryops, and that tree produces leaves,
shoots, flowers and fruit seemingly normally.

I did considerable search on the web for "euryops
pectinatus" + allelopathic/allelopathy, and I couldn't
find anything definitive.

Any information appreciated.