Baron’s green racers (Philodryas baroni) are 4.5-6’ long, arboreal snakes primarily found in Argentina, Bolivia, and Paraguay. Although they seem like a tropical species, they actually prefer a semi-arid habitat.
Baron’s racers have slender bodies, elongated pointed heads, round pupils, smooth scales. They’re best known for the nubby horn-like protrusion from their snout. This species is best known for their leaf green coloration, but some localities are brown or even blue! The underside is pale, and there may be a thin black stripe between the dorsal and ventral colors.
Baron’s racers aren’t the best choice of reptile for someone who wants to handle their pet on a regular basis, as they generally prefer to be left alone, and they are mildly venomous (but not dangerous to humans). However, their unique appearance does make this species an excellent display animal.
Minimum terrarium size for Baron’s racers
The absolute minimum terrarium size for a single Baron’s racer is 5’L x 2.5’W x 2.5’H. Of course, larger is always better! These snakes may look small due to their slender bodies, but the fact is that they still need enough room to stretch out fully, explore, and hunt.
Cohabitation (keeping multiple Baron’s racers in one enclosure) is not recommended.
Do Baron’s racers need UVB?
Technically they can survive without it, but we still recommend providing appropriate UVB lighting to Baron’s racers. UVB lighting helps provide a clear day/night cycle, provides all of the vitamin D that your pet needs, strengthens the immune system, facilitates better digestion, and provides other benefits.
The best UVB bulbs for Baron’s racers in a 2.5’ tall enclosure are:
- Zoo Med Reptisun T5 HO 5.0
- Arcadia Forest 6%
For best results, use a UVB bulb roughly half the length of the enclosure and housed in a reflective fixture by Vivarium Electronics or Arcadia. Position the lamp on the same side of the terrarium as the heat lamp, about 9-11” above the basking branch and protected by mesh.
UVB is blocked by glass and plastic, so placing the terrarium in front of a window doesn’t count as “free UVB” — in fact it can make your terrarium too hot due to the greenhouse effect. Don’t forget to replace your bulb every 12 months!
It is also recommended to install a 6500K T5 HO fluorescent or LED grow light to span most of the enclosure’s length. This is essential for facilitating healthy plant growth if you are using live plants, and also helps create a distinct day-night cycle.
Lights should be on for 13 hours/day during summer and 11 hours/day during winter.
Best temperature for Baron’s racers
Like other reptiles, Baron’s racers are cold-blooded, which means that they rely on external temperatures to manage their own body temperature and metabolism. A reptile’s enclosure should offer a range of temperatures to allow them to thermoregulate effectively.
Specifically speaking, Baron’s racers should have a basking surface temperature around 90°F. In the lower levels of the enclosure, the temperature should be 75-85°F. Temperatures should drop at night, but no lower than 68°F. You can check your temperature gradient by placing one digital probe thermometer on the basking surface and another in the shade on the other side of the enclosure.
Provide heat for your snake with a cluster of at least two incandescent heat bulbs, placed close together over the basking area (ex: a piece of flagstone or stone paver) to evenly heat the snake’s entire body. Do not use ceramic heat emitters (CHEs), red bulbs, or blue bulbs, as these are not as effective. If the bulbs are a little too hot, use a plug-in lamp dimmer to reduce output. If the bulbs are not hot enough, you will need a higher wattage.
Best humidity levels for Baron’s racers
Baron’s racers are a semi-arid species that requires average humidity levels under 50%. Humidity should be at the lower end of this range during the day, and higher at night. You can track humidity with a digital probe hygrometer, with the probe placed in the middle of the enclosure.
That being said, Baron’s racers generally prefer to get their water from droplets on leaves and other surfaces rather than from drinking out of a bowl (when available). Lightly mist your snake’s enclosure 3-6x/week with a spray bottle to meet this need.
We also recommend installing a humid hide for your snake, lined with moistened sphagnum moss, somewhere in the enclosure.
Best substrate for Baron’s racers
Providing a thick layer of naturalistic substrate (“bedding”) will help maintain correct humidity levels and helps make your enclosure more attractive! Based on the conditions of their natural habitat, we recommend the following substrates for Baron’s racers:
- Zoo Med Excavator Clay
- Zoo Med ReptiSand
- Exo Terra Stone Desert
- Exo Terra Desert Sand
- Exo Terra Riverbed Sand
Layering clean, chemical-free leaf litter on top of the substrate can also help with humidity.
Substrate should be 1-2” deep and completely replaced every 3-4 months. Remove poop and urates daily, along with contaminated substrate.
How to decorate a Baron’s racer terrarium
An empty terrarium makes for a bored snake, reducing its quality of life. Keep your pet entertained and engaged with its environment with the strategic use of décor items that encourage it to exercise natural behaviors!
Since Baron’s racers are arboreal, it is extremely important to provide branches for your pet to climb and perch on. However, here are some other ideas to fill out your setup:
- cork tubes
- drought-tolerant live or artificial plants
Make sure that your snake also has covered areas to retreat to when it wants privacy. Foliage (live or artificial) works very well for this purpose.
What to feed to a Baron’s racer
Baron’s racers are carnivorous, which means that they need to eat whole animal prey in order to get the right nutrition. Here’s a general feeding schedule to get you started on the right foot:
- Hatchlings should be fed once every 5 days.
- Juveniles should be fed once every 7 days.
- Adults should be fed once every 7-10 days.
Appropriate prey items for pet Baron’s racers include mice, rats, quail, chicks, and frog meat. Prey should be smaller than 1.5x the snake’s widest point, or the meal should consist of enough smaller prey items to add up to less than 10% of the snake’s weight.
Although live prey can be offered, it’s best to use frozen whenever possible. Prey should be thawed in a BPA-free plastic bag in warm water until it reaches room temperature, then use a pair of soft-tipped feeding tweezers to offer it to your snake.
Snakes can survive without dietary supplements, but using them every once in a while can help prevent your pet from developing a nutritional deficiency, helping it live healthier. We recommend Repashy Calcium Plus LoD, lightly dusted on the prey item before offering.
Make sure your snake always has a source of drinking water, provided via medium water bowl. It doesn’t need to be large enough for soaking. Keep the water clean and free of debris, and scrub the bowl with a reptile-safe disinfectant weekly or whenever it becomes soiled.
How to handle your Baron’s racer
Reptiles generally don’t appreciate petting and handling in the same way that dogs and cats do. Some Baron’s racers don’t mind handling, while others are best left alone. Get to know your pet as an individual and act accordingly.
When picking up your snake, be gentle and try to pick it up from the side or below rather than from above. Support as much of its body as possible, but don’t squeeze it or restrain it too much — let it move and explore, which helps it stay calm. NEVER pick it up by its tail, as this can damage its spine!
Note: Baron’s racers are mildly venomous. This venom is not considered medically significant to humans, but it can potentially cause short-term localized swelling. Fortunately, bites from Baron’s racers are pretty rare, but if you are nervous about getting bitten by your snake, wear a pair of thick leather gloves during handling.
*This care sheet contains only very basic information. Although it’s a good introduction, please further your research with high-quality sources. The more you know, the better you will be able to care for your pet!
"argentinian long nosed tree snake" by Cloudtail the Snow Leopard is licensed under CC BY-NC-ND 2.0.