We’ve been noticing a trend that has been increasing at an alarming rate in the isopod community- that people aren’t terribly fond of using a large number of leaves in setups. We get it- lots of leaves means lots of hiding places and less of an opportunity to see the isopods. For some people, there is the question of availability, as ordering in leaves can be very expensive if you are unable to collect from your local area. However, we strongly urge you to use a generous number of leaves in all isopod setups – this is the key to getting isopods to thrive, and a lack of leaves, in most cases, directly contributes to colony crashes and die offs.
The first, and most important aspect of leaves is that they are the primary diet of all terrestrial isopods. We’ve discussed supplementing diets with wood, protein, and calcium – but the majority of an isopod’s diet is and always will be leaves. No amount of supplementation or substitutes can replace what leaves offer for isopods. Some companies offer a “highly nutritious” substrate mixed with a variety of plant foods, rotten wood, and other nutritional additives, while isopods do benefit from these substrate mixes, they still cannot replace the portion of their diet that should be leaves.
So, you’ve got a good handful of leaves in the setup for them to eat- will this be enough to replace as they eat it? Unfortunately, no, it will not. Beyond leaves being a basic part of isopod diets, they serve several other purposes as well. A setup should have a thick layer of leaves covering the entirety of the setup – substrate that is exposed to air without the cover of leaf litter is essentially pointless because isopods won’t use that area. Leaves provide cover for isopods to go about daily isopod activities; with security there is less stress, more successful breeding, brooding and birthing of babies and overall growth of the culture. Babies and adults alike use leaf litter as hiding areas – leaves effectively multiply the available surface area for isopods to live in a setup. We recommend using at least 1” of leaves covering all substrate- for all isopod species, no exceptions.
Another very important aspect of leaves is that they add a layer of insulation to hold in moisture. Without leaves, a setup may dry up within days, killing the isopods. Setups with 1” or more of substrate and 1” of leaves can go over two weeks without adding moisture, because leaves both absorb the moisture, and reduces air exposure to the substrate, so it retains the moisture longer as well. A dry setup for isopods is a death sentence – so a nice layer of leaf litter is a good security measure to prevent isopods from drying out.
What about moss? Well, too much moss can be detrimental. While isopods can eat moss as well – they don’t use it as a constant and continuing source of food, leaves are much easier for them to eat and break down. While we don’t have an exact nutritional breakdown, there are structural differences between moss and leaves as well. Moss also absorbs and holds moisture more effectively than leaves or soil, so a setup that is mostly moss can become too moist and humid very easily. When humidity and moisture are too high, isopods have difficulty shedding and may die mid-molt. It’s comparable to how difficult it is to peel off wet clothes after a heavy rain. If it is preferred to use moss as a safeguard to prevent a setup from getting too dry, a 1”x1” corner is really all that is necessary to use. Any more is taking away available space for leaves from the isopods, as well as keeping in too much moisture.
What kind of leaves are best? We prefer to use thinner leaves in our setups. It’s a mix of what is regionally available, and what isopods prefer. An example of what would be a “thicker” type of leaf is magnolia leaves; while beautiful, these leaves are very thick, firm, and take a long time to break down. They seem to have an extra layer to the leaf preventing moisture absorption and breakdown. Magnolia leaves are excellent for an aesthetic look and resistance to mold, but we’ve found that our isopods don’t really seem to enjoy eating them.
The key to an isopods’ diet preference is in their mouthparts: they have to chew through leaves to consume them. A large population is very efficient at this, but an individual wears down its mouthparts over time and prefers to have a softer food source to preserve them. That’s why thinner leaves do better as a food source; it’s something that absorbs water, decays more quickly, and softens easily. An elm leaf that has been soaking in water will easily pull apart in your hands, for example. For these reasons, we recommend sourcing and using thinner leaves for isopods for best results. We’ve had a large success with leaves from trees such as elm, maple, linden, apple and willow trees. Oak and cottonwood are readily accepted but are much thicker than the previously mentioned leaves and take a long time for isopods to eat. We’ve had the least success with leaves such as magnolia.
Leaves serve a very important role for isopods. They are food, security, and a home. To get your isopods to thrive, the first and most important step is to make sure there is an abundant source of leaf little for them to frolic through and consume.