Seeing the announcement about the Sebastopol Walk beginning at the Laguna Preserve, I have to ask:
How many people are aware that the Laguna Foundation applied the herbicide Telar XP to several carefully chosen spots in the Laguna Preserve? Their target is invasive pepperweed. I've been trying to learn exactly where the spray was applied, and have somewhat conflicting information from different sources. I'd seen some pepperweed near the trail to the left as you come off the seasonal bridge, but I don't know if the Telar XP was used there.
There were warning signs right after the spraying, but I believe those have been removed, with the erroneous thought that the spray "is only dangerous for a day or two." Actually Telar XP has a half life of 1 to 3 months, which means it will be present in the area for as long as a year. [Another source says two years.]
Telar XP is supposedly "relatively nontoxic" to humans, but given how long we were told Roundup was "safe," I wouldn't put much stock in that assessment. The literature I've had time to review suggests the studies are inadequate at best.
In any case, Telar XP, even according to the manufacturer, should NOT be used in wetlands. The Laguna Foundation has decided that since it was applied when it's unlikely to rain for a while, it should be ok. But given the half life [Four times the half life is what it takes for a chemical to be "essentially gone."], we can count on it contaminating the water. Then there's the question of its breakdown products are. Often, the breakdown products are more toxic than the original pesticide, and accurate information about breakdown products is very hard to come by.
There are two issues: 1. be aware of possible herbicide exposure if you travel the Laguna trails; 2. maybe it's time to require the Laguna Foundation to protect the Laguna from poisons, rather than add to them.