georgf
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small white grubs in my compost heap

my compost heap has a lot of small white grubs in it, about 1/4 inch by 1/2 inch long (or less). Are they harmful to plants, seedlings, or eating roots? I must admit that the heap has an unpleasant odour which I attribute to anaerobic conditions in the middle, and could attract flies etc.

and the second question. Some customer apparently found a worm by the name of "hammer head worm" in the compost I am selling. This worm is said to live on earth worms, to the tune of eradicating the population in no time. I have never seen such a worm and my earth worm population is healthy as ever. Who's got more info on these critters?

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rainbowgardener
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I had never heard of the hammerhead worm, so I looked it up.

Here's a picture:

[url=https://www.google.com/imgres?imgurl=https://pics.davesgarden.com/pics/2008/09/19/organic1/3e477b.jpg&imgrefurl=https://davesgarden.com/guides/bf/showimage/7486/&h=534&w=878&sz=118&tbnid=F_-D0wznozU6_M:&tbnh=89&tbnw=146&prev=/search%3Fq%3Dhammerhead%2Bworm%26tbm%3Disch%26tbo%3Du&zoom=1&q=hammerhead+worm&usg=__DqbVY0oYGOdFirhHofRZVO7Vgtw=&sa=X&ei=cCuiTabhF4Xp0gHQquGcBQ&ved=0CCgQ9QEwAg]hammerhead worm[/url]

I think if you had one of those you would know it, since they supposedly get up to 20" long and are commonly 10" or more. And you likely wouldn't have just one, so you can check your compost to see if there are any more. But it does sound like something you would NOT want in your garden.

The white grubs are likely beetle larvae, maybe Japanese beetles or some relative. They do eat roots and then the beetles hatch out and eat leaves. They are bad guys. I don't have lots in my compost, but I do find the occasional one. They are easy to hand pick or sift out and they don't move very much. I just pull them out and throw them onto hot concrete patio that they can't burrow in to, where they become bird food.

For the anerobic conditions and smelliness, add some more browns (see the greens/browns sticky at the top of this Forum for suggestions) and turn/mix thoroughly. Should take care of it.

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farmerlon
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georgf wrote:my compost heap has a lot of small white grubs in it, about 1/4 inch by 1/2 inch long (or less). ...
Without a picture, I can't say for sure; but, if it's not a "grub", it could be Solder Fly Larvae.

To my knowledge, Soldier Fly Larvae are harmless in the compost, and are actually a valuable "shredder" of the compostables.

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rainbowgardener
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But the BSF (black soldier fly) larvae are not white. They are a dark greyish brown. I'm familiar with them, because I have had some in my worm bin.

This thread about my worm bin has a picture of the BSF larva:

https://www.helpfulgardener.com/forum/viewtopic.php?p=177443#177443


Here's a picture of a japanese beetle grub:

https://plantdiagnostics.umd.edu/level3.cfm?causeID=385

(you have to scroll down a little)

But yes, if it is the BSF, not to worry, they are part of the breaking down cycle in the compost pile.
Last edited by rainbowgardener on Tue Apr 12, 2011 12:48 am, edited 1 time in total.

toxcrusadr
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BSF do tend to show up when things are too wet and/or too rich in nitrogen. Having larvae at the same time you have a smelly pile is pretty good circumstantial evidence that they are BSF. I would turn that pile and add some dry browns to it.

I have never heard of that hammerhead worm, sheesh!

rot
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..
Namibia - you're in the tropics and those grubs could be a variety of things we may never have heard of. Seek out some local agriculturist type to help.

That hammer head thing is probably a flatworm of some type and they are predatory. The ones I've seen don't get quite 10 inches (25 cm) but I imagine there are a great variety of the species. The link I found didn't offer much hope.

https://www.redwormcomposting.com/reader-photos/predatory-flatworm-bipalium-kewense/

Search on the latin name, bipalium kewense, and maybe you'll find some tactics to try out. It may be just a matter of introducing another predator for that predator. I'd expect that some ants might wipe out a lot worms but they'd really do a number on those flat worms.

Good luck
..

toxcrusadr
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Holy cow, I missed the fact that our poster was in Namibia! Would that be our farthest away member? Besides Australia I suppose.

Yep, your grubs could be something entirely different from American grubs... :D

Bobberman
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Great pictures guys I really enjoyed these post!

georgf
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After mulling over this grub business for a considerable time, I have come to the conclusion that this are larvae of dung beetles, who layed the eggs into the dung pats we have collected. But this leaves me with only one answer, that the pile never gets hot enough. Not that I dislike these worms, but try selling this compost to a towny and hear him protest?
Question now is how to increase the temperature? The highest I got was 60°C. What needs to be increased - green or brown?

rot
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60 degrees C is pretty good if you're maintaining over some days.

Don't know a thing about what or how you're composting so it's kinda hard to say how to get it hotter. For hot composting you typically want a volume of a cu yd or cu meter minimum. Then you want the optimal mix of high nitrogen and high carbon materials. I wouldn't know the optimal mix if I saw it because I'm just using what I have on hand. Then you need to make sure you've got the right level of moisture. Then for the fastest compost you need to turn it on a regular basis. I remember some study came up with turning every 4.5 days was the optimal.

After you get all the tips and techniques from elsewhere, you'll need to adapt all that advice for your climate and your ingredients.

If you want to up the heat start looking here:
https://compostinfo.com/tutorial/ElementOfComposting.htm

If you're really serious, look here:
https://compost.css.cornell.edu/index.html

Handy dandy list of ingredients and their C:N values here:
https://compost.css.cornell.edu/OnFarmHandbook/apa.taba1.html

to sense
..

georgf
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Thank you very much, this was really helpful. I now need to apply and see.



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