All parts of this plant, including seeds, are poisonous to ppl and even to cattle, except goats :) Many ppl are also allergic to latex that plant produces. This is true to many euphorbias in various extent, and at the same time - many are very nice looking plants - and being grown and sold in nurseries. Many are also considered invasive in some regions...

Euphorbia lathyris, aka caper or gopher spurge. A pretty weedy annual/biennial species. And has little to no effect on gophers or moles :-)

Beware: in a year you have a hundred; two years a thousand etc.

Rina, it's a good thing it's not a succulent E. myrsinites!

gg, presumably voles as well (which is what we have here)?

It looks like a beginning Oleander, too, and sounds about as nasty to human interaction.

Many hardy euphorbias are wonderful garden plants and are no more dangerous to handle than scores of other plants with toxic properties!! And by far less dangerous than oleander! Personally, I find a garden without some sort of hardy euhorbia seriously lacking :-) But some species are indeed very aggressive spreaders, to the point of being considered invasive in certain locales.....like Euphorbia myrsinites here in WA state.

gg, when you wrote 'far less dangerous', how do you mean? I hadn't compared the two before, other than knowing about the all-parts-toxic bit about the nerium (and beyond having pruned a lot of Nerium oleander, and even more tall, columnar Euphorbia, like 20' E. ingens, resulting in only a few minor burns, thankfully), but the Nerium was by far the lesser leaker of caustic sap than the Euphorbs were.

Caustic sap is one thing :-) And one may or may not be overly sensitive to it. With all my years of growing euphorbs, including a few tropical species as well, I have never been affected by the sap. But even ingesting the sap is unlikely to kill you with 99% of the euphorb species

OTOH, cardiac glycosides are an entirely different ball of wax and puts oleander right up there with some of the most toxic plants we grow. Even the smoke from burning oleander can be fatal if breathed in.

Right! I had forgotten that it packs that extra punch. IIRC, Barbara Kingsolver's novel The Poisonwood Bible is thought to be referring to it in its title.