Stem Infested

Something is burrowing into the stems, bulging them and leaving deposits

They have been getting dry sprayed with vegetable dust every few days, especially after rain, since they went outdoors

What can I use to stop future infestation?

Thanks

I had this same fucking problem last year, lost my nuggies
Uhmm I would try using some sort of plant tape where they burrowed and hope for the best.
It was such a bummer cracking the stock open to find little cob webs, hollow stock and little black bugs..
Hope thats some help