- ShadowCat owns both attachments and will help you decide which attachment is best for the job and budget that you have!
As for the difference, it's in the name and it's in the price of the equipment!
The average Bushhog attachment cost from $3,000 and top out at around $10,000. A forestry mulcher attachment STARTS at $30,000 for the attachment!!! That is one reason you see many Bushhog operators but few Forestry Mulchers.
Blades on a bushhog cost $40 each and there are only three of them. Teeth on a forestry mulcher cost $120 each and there are thirty teeth! That is the second reason you see many Bushhog operators but few Forestry Mulchers. The replacement teeth alone will cost more than the purchase price of some bushhogs in just one year of operation.
A Bushhog primarily is used for tall grass and small bushes. You see farm tractors on side of the road cutting grass... they are pulling a bushhog. Bushhogs can also be pushed, such as my bushhog shown below. However, a bushhog cannot mulch! Bushhogs are three bladed mowers, similar to a lawn mower so they are limited in performance. They can cut down small 1-2 inch diameter trees but you will have large pieces everywhere vs mulch. Bushhog manufacturers claim to be able to cut through up to 12 inch trees... this is false. My Diamond bushhog is limited to around five inch diameter trees (cutting, not mulching) and the results are horrible. The Diamond bushhog is one of the largest bushhogs and cost over $10,000... so compare that with people using $4,000 bushhogs and you can expect poor results.
A Forestry mulcher is used to mulch bushes, small trees, palmetto plants, general overgrowth, etc. Forestry mulchers are great at mulching up to six inch diameter tress. They can go higher, but the reality is that is more marketing by the manufacturer than reality. While a bushhog cannot handle palmettos, a forestry mulcher slices through palmettos without a problem. Typical Florida overgrowth is no match for a Forestry Mulcher and the pictures in my Before/After galleries are all from Forestry mulching. Pepper trees, palmettos, medium size trees, etc are all Forestry mulcher only type of growth.
A Forestry Mulcher also can only be operated by a large machine with high flow hydraulics. Smaller machines simply do not have the power to lift the attachment or run it at proper speeds.