Sorry, i dont know the agave id, but i do have the euphorbia weeds. Dont know what those are either, but they are covering my yard!they grow out of every crack, and crevasse and alot grow in my cactus garden, which gets watered once a week and they get massive. Sometimes they even go and cover a whole cactus (in the area i dont pay attention to) and it is a pain to get the weeds off. Literally ... if you look closely they have cute little white and purple flowers. They also shoot hundreds of seeds everywhere and start sprouting ... bad little buggers those are

Here is a close up of the Agave.

Too many agaves look alike to me, sorry, but I too get those weeds. I din't know they were in the Euphorbia family. Thanks.

It is an Agave montana. A very nice agave in my humble opinion. I have several because they are highly variable. For me cold hardy but not for you. But it can be one of the last to make the trip inside and one of the first to come out in the spring. It is said to be hardy to at least Zone 8 but some say a lot more. It all depends on how high up the mountain the seed was collected.

Put a montana in in the ground last year; we got down to 10 degF several times in mid-winter; it looked good coming into spring, but as soon as the weather began to warm in May it rotted. The snow may have been worse than the cold.

As for Euphorbia, I tried to weed my dear wife's Euphorbia out of my Penstemon bed--I woke up at about 11 that night with terrible burning in my eyes; took several hours before I could get back to sleep--I don't touch it anymore

That was my experience with aA. weberi that nudged its hardiness rating of 15. I think the rot starts in the roots and works up. My sharkskin met the same fate. Also the first winters that it is in the ground the agaves should be treated as delicate. It takes a while for them to get hardy. so protect them for a couple of years.

Thanks! Agave montana does seem like a nice plant. Reading online, they might like more rain or shade than normal, not a full bore sun desert plant. I had it out in full sun. The patterns on the leaves are permanent imprints from the teeth when the new growth is curled up.

It can take more rain in the summer and it is from a cool summer area, or cooler that my Central Texas summer. It does not much like a whole bunch of humidity. Also it's cold hardiness is reduced by dampness. They are a new plant in the trade so facts are still very variable. Some people are growing them in 6b and others are killing them in in 7b so be aware that either there is cold dampness killing them off, or their is variability in the species, or people planted them out and they were not able to slowly establish hardiness before winter hit. I have heard of people growing them in mountain areas of North Carolina.

In nature they grow in a arid pine forest high on a mountain in Northeast mexico just south of Monterey in Nuevo Leon. The canopy of the pines look thin so they do get sun, probably acid soil but mine will take amended alkaline.

I have included my post of my many variable plants and embedded in that is a site that shows habitat.

Here is a link that might be useful: Agave montana comparison