http://www.butterfliesandmoths.org/species?l=1372&chosen_state=48*Texas
Eastern Tiger Swallowtail (Papilio glaucus)
They list the same old host plants for each state:
Caterpillar hosts: Leaves of various plants including wild cherry (Prunus), sweetbay (Magnolia), basswood (Tilia), tulip tree (Liriodendron), birch (Betula), ash (Fraxinus), cottonwood (Populus), mountain ash (Sorbus), and willow (Salix).

http://www.npsot.org/Austin/PlantLists/mirror/LarvalHostPlants.html
Eastern Tiger Swallowtail
Escarpment Black Cherry (Prunus serotina var. Exemia)
Texas Ash (Fraxinus texensis)

http://www.dallasbutterflies.com/Butterfly%20Gardening/Host%20Plants%20by%20Common%20Name.htm
This is a good list, just search on "Tiger"

http://www.docstoc.com/docs/46871990/Butterfly-plants
Another central Texas list of host plants.

Here is a link that might be useful: Butterflies for Bexar County, Texas

Hi, I live not too far away...in Medina Co. I've had Tiger Swallowtails use Escarpment Black Cherry and Texas Ash. Lucky for me, the cherry trees grow wild here, but the native ash tree I planted years ago. BTW, check the tails on those tigers. The Two-tailed Tiger Swallowtails also come into your area sometimes. This spring there were caterpillars of that second kind all OVER the place! More than I've ever seen. Just released the first-emerged of those butterflies the other day.

Wow, that is great to hear! I would also love to hear what you use for other caterpillars since you are next door, especially if you've discovered any great natives that are not commonly associated with their caterpillars.

Here is a link that might be useful: {{gwi:507128}}

Well, here's a few of my host plants:
Common Hop Tree is used by both the Giant Swallowtail and the Two-tailed Tiger Swallowtail around here.
My Escarpment Black Cherry trees are used by the Tiger Swallowtail, Two-tailed Tiger Swallowtail and the Red-spotted Purple.
Right now the native Plateau Agalinis is up and looking good, but I haven't seen any Common Buckeye cats yet...although the butterflies have been around recently.
Spicebush...well, that one is obvious, Spicebush Swallowtail.
Velvetleaf Mallow (Allowissadula holosericea)...I've discovered that this native plant is a host to skippers, mainly the Texas Powdered Skipper.
Common Sunflower or Zexmenia (Zexmenia hispida)...on occasion the Bordered Patch will use them...right now the cats are on the Sunflower.
Mexican Milkweed and Texas Milkweed (Asclepias texana) for Monarchs and Queens. The only things that have eaten any milkweed so far this year are some beetles...really pesky things. Hopefully the Queens will lay eggs soon.
I'll have to think about the rest. Kind of late right now.

Sahmbo,

I tried to email you back, but your account wasn't accepting replies. You are welcome for the help. Glad that Linda a fellow Texan could give you some good information. All I can do is searches on Google.

Yes...I thought that was pretty good research, runmede!Corona de Cristo, Passilfora foetida var. gossypifolia, that is for the GF's
Maypop for the GF's and the VF's too. Also the Zebra Longwings when we're lucky enough to get any.
Blue Passionflower, P. caerulea for the GF's and Zebra Longwings.
Also P. lutea and P. affinis for those two...as you can imagine, my yard is overrun with passies...and GF's!
I've got some native Blue Flax, Yellow Flax and Rock Flax...used by VF's.
I've got aristolochias...just two A. erecta and some A. serpentaria and A. fimbriata. Pipevine Swallowtail don't often use them real often, but sometimes they do.
Italian parsley and two types of garden fennel for Black Swallowtail. I also have two types of wild parsley (Daucosma and one I haven't ID'd) and something that might be a wild dill.