Looks like one of the ligustrums

My guess is that it is Stenosiphon linifolius also known as False Guara. I have only seen it in the fall when it is STILL blooming but much tangier and tall. It is a sand out in the grasslands. I collected seed of it in September but the deer ate it. I have seen its growing at LBJ Wildflower Center.. Very cool plant. They are not a common plant in my corner of the hilcountry . Much more prevalent to the north of me..

Looks way bigger than any Camassia I have seen, and mine always bloomed earlier in the season, like May. But I do not have any suggestions since I have no experience with TX plants.

Looks a lot like Persicaria pensylvanica. We have 16 native species of Persicaria in NA.. We have about 2 species native Bistorta. B. amplexicaulis is cultivated here, but hasn't escaped and naturalized.