What safe wood stain can I use for my bearded dragon's enclosure?

Firstly remove all small branches and leaves. The safest method is putting the wood in the oven if it fits. You need to put it in at 200F and cook for 2 to 3 hours, do not leave unattended. You can soak bigger pieces for 24 hours in a cup of bleach to 1 gallon water solution in the bath. Then you must rinse thoroughly and repeat the soaking at least 5 times in clean water to remove the bleach. Then air dry the wood. Obviously the bleach has to be properly removed. Personally I would use the oven method and if not just buy ready made wood from the pet shop.

If the wood stain is water based there should be no problem to use it in the same room. The same is true for water based paint., Your bird should have no access to the painted surfaces until they have dried completely. It would be best to put the cage into another room for 2 or 3 days.

A silicone adhesive/sealant specifically for aquaria would be best. These are strong, durable and fish/reptile safe. You can find it in most home improvement stores. GE SCS1200 silicone is also reptile safe once cured/dried. It can also be found in home improvement stores and hardware stores.

Cats will often scratch and ingest the dust from timbers and scratching posts as they groom their feet. This is completely natural behavior and is no concern with untreated timbers. I would be sure to use a non-toxic tree and would not use any sealers or varnish

You can use a pet safe sealer/varnish. Rats need to chew to keep their teeth from overgrowing, so be sure to provide plenty of chew toys so they don't turn to the wood. Do not use cedar, pine or yew as these can cause health problems. Allow an adequate drying time once the wood is sealed.

Bearded dragon owners can also add plants to the habitat, but take care when adding real plants. If a live plant is in the habitat, the bearded dragon might decide to use it as a snack. If the plant is toxic to bearded dragons, your pet could end up very sick, or dead. Artificial plants are the best option since they are easy to clean, never need water, and are very naturalistic. Most pet stores carry a wide variety of artificial plants to choose from. If you decide to use live plants, junipers are one of the most recommended plants to use. Junipers are slow-growing and do not require much water.

Thanks for your question about Smaug, and thanks for the photo as well! I think that you have a good start to your set up, and that we can tweak a few items. First, your lighting situation appears adequate - I see a UVB light (please change this bulb every 4-6 months), a basking light, and a ceramic heat bulb. I would ensure that your temperatures are appropriate for this species, and that you are monitoring them using digital thermometers (I think that you see both a digital and analog thermometers currently) at the level of Smaug. Analog thermometers are inaccurate, so I don't recommend using them (also, they are high up on the sides of the enclosure, so they wouldn't be giving an accurate temperature read for Smaug). For the cage furniture that you have, I like that you have places for Smaug to climb and hide. However, I would recommend having a hide on both the warm side of the enclosure and the cool side so that Smaug has choices. Same for the climbing structures. I may have missed a food and water dish in the enclosure - I would recommend that both of these be shallow, and be large enough for Smaug's entire body to fit within them. I cannot tell what type of shavings that you have on the bottom of the enclosure, but the only wood shavings that I recommend are aspen shavings. If they are pine, these can be irritating to the respiratory system. I hope that gives you a place to start, and thanks for using Petco Pet Education Center, formerly Petcoach!