Baking substrate as sterilization technique?

[charx53]

Hello everyone!

 

So I was curious if I scavenge around for decayed wood, if it is better to bake it or leave it as such when creating my initial substrate?

 

Does baking it take away any nutrients that the beetle larvae could use when they eat it? And if so, any ideas to replenish it? I've heard something about using flour, kind of as you would ferment wood pellets by adding flour and yeast.

 

I think I would personally prefer to bake the wood to get rid of pests as I fear mites or anything infesting my larvae. I have baked decayed wood at 250 for about twenty or so minutes then mixed it with compost soil for my substrate base. Any comments or suggestions would be much appreciated!!

 

Thank you all!

 

-Charles

[Shade of Eclipse]

I pour boiling water into my substrate, mix, and then allow the excess moisture to drain. Baking can burn the substrate and make it unpalatable and is often not as effective at heating large volumes of substrate unless you bake for a long time--further risking burning and creating a fire hazard as well.

 

If you're concerned about water leeching nutrients from substrate, keep in mind that rotting wood and organic soils are normally exposed to elements such as rain and would be subject to having things leeched out of them naturally. Also keep in mind that any free nutrients in substrate would immediately be taken up by microbes or other invertebrates and would not normally be readily available for long, so there is no reason to be concerned with washing away nutrients or having to add any if the wood is properly decomposed.

[Garin]

Good info Shade. Adding boiling water seems like a very efficient and fast way of sterilizing substrate. How much substrate are you able to do at a time? I would think maybe about one or two gallons? After you mix the boiling water, how do you drain the water? I have had issues when I add alot of water to sterilize and then it takes many days to dry out to a suitable moisture level.

Thanks.

[Shade of Eclipse]

I use large buckets and process a few gallons of substrate at a time. After it's been mixed to ensure that everything's been exposed to high heat, I leave it to sit until it cools down and use a large piece of cloth to get most of the excess water out by placing it and keeping it over the top of the bucket and flipping the bucket over. The rest of the excess water can then be squeezed out by using the cloth to wrap up large portions of substrate and applying pressure.

[Garin]

Great method. What do you use to boil such a large amount of water. I guess a huge pot?

Thanks

[charx53]

Thank you for this Shade and Garin! I suppose I wonder if I got such decayed wood that it is literally like a soil consistency that if I was to put boiling water to sterilize that it seems it'd be difficult to dry it out at that consistency. But it is more or less just a process and is completely doable. Thank you!

[Shade of Eclipse]

I use a nice, big stew pot. You don't need that much water since the substrate already takes up plenty of volume in the bucket.

If you're doing this to a soil-like substrate, you'll just need a finer cloth to catch all the particulates so they don't drain away. You can use a cheesecloth or a canvas bag for something sturdier.

[Garin]

Thanks for sharing. I am surprised that just pouring the boiling hot water is enough to sterilize the wood. I always thought you had to boil it for awhile. It's always good to know what works in the practical world.

 

charx53, you can also spread out the substrate on a mat and it dries out a lot of faster than leaving it in a bucket.

[Shade of Eclipse]

It isn't sterile, but it does rid the substrate of a lot of problems. Without high temperatures and pressures of an autoclave, you're unable eliminate many cysts and spores.

[Garin]

Yes, but it sounds like for practical purposes it does what we need it to do.

Thanks!