That Reptile Blog – Reptile, Amphibian and Exotic Pet Care and Information

Live plants are very useful in creating amphibian terrariums that are both attractive to the eye and beneficial for the animals housed therein.  However, amphibian skin is permeable to substances as small as oxygen molecules.  Several readers have recently questioned whether pesticides used on terrarium plants could harm amphibians through physical contact.

Examples of Contact Poisoning

Most chemicals do readily penetrate the skin of frogs and salamanders and can kill them in short order.  Pesticides on plants are a concern, even though they will not be consumed.

A coworker of mine once lost a group of Blomberg’s Toads and Smoky Jungle Frogs after confining them to quickly-rinsed enclosure that had been cleaned with Nolvasan, and I witnessed a Leopard Frog expire after being put into a pail that had previously housed a Fowler’s Toad (the stressed toad had apparently released skin toxins).

Locating Safe Plants

Some commercial growers who cater to zoos and the pet trade claim not to use pesticides.  The reptile department of your local zoo, if reachable, might be a good place to start when searching for reputable plant suppliers.  Pet stores specializing in tropical fishes usually buy pesticide-free plants as well. Some, especially those that carry plants for outdoor ponds, may stock emergent species or others suitable for use with amphibians.

Removing Surface Pesticides

If you are unsure of pesticide presence, discard the soil that arrived with the plant and rinse the plant, roots and all, vigorously.  Finish up by submerging the plant and swishing it about underwater.  Some recommend a light soap solution, but I have not found this to be necessary.

Systemic Pesticides

A greater potential concern is posed by systemic pesticides, which do not remain on the surface but rather work their way into the plant’s tissues.  Fortunately, these are not commonly used with on commercially raised plants suitable for terrariums.

One colleague of mine did run into a situation involving systemic pesticides.  He held the plants for 30 days before introducing them to his exhibits.  He had no problems with any of several tree frog species that utilized the plants frequently, and eventually used them with arboreal salamanders (Bolitoglossa spp.) as well.  This time frame is based on observation rather than rigid testing, but has proven quite dependable.

Further Reading

Those who keep herbivorous turtles and lizards also need to be concerned about potentially lethal plants.  The species listed in my article Common Plants that are Toxic to Birds  should be avoided by herp keepers as well.

To learn about growing safe plants for herbivorous reptiles, please see Reptile Gardens.

In my own tanks and those I design for zoos and aquariums, I have long been fond of featuring exposed root systems.  I am also drawn to what used to be termed “shoreline terrariums” – exhibits highlighting shallow water fish and semi-aquatic amphibians, reptiles and invertebrates.  Zoo exhibits are often quite deep and not always equipped with lighting that meets the needs of aquatic plants, so water-tolerant land plants often fulfilled my needs.

One species I have come to depend upon is the Peace Lily, a common house plant.  Its genus contains over 40 South American and Southeast Asian species, and the leaves are fairly “generic” in appearance, and so the plant handily fits the themes of a wide range of exhibits.  I prefer the “Mauna Loa” strain, which is readily available and amazingly resilient.

Most Peace Lilies prefer slight shade, but thrive under lights and tolerate fairly dry to wet soil. In my opinion, they really come into their own, terrarium-wise, when planted or suspended in water.  They thrive for years this way, and send out truly impressive root systems in short order.  Fish, shrimp, crayfish and snails will spend hours foraging among these, and the roots also have a beneficial effect on water quality.  Their intertwined tendrils provide vital shelter to young fishes and shrimp, and lend a stunning look to planted aquariums and terrariums.

As you can see from the accompanying photo, the sturdy leaves function almost as do water lily pads, and easily support the weight of an adult Green Frog.  The other photos depict a Southern Leopard Frog resting on a leaf draped over a stump, and the extensive root system that was formed from one small plant (5 leaves).

I have even seen Peace Lilies sold for use as totally aquatic plants, but have not tried planting them in this way.