My woodworking dictionary says Fender is fender. A Fenderpfahl is a fender pile. Possibly, these are skids (trail slides) used for transporting timber. A Kantel is a square piece of timber. In the US, we'd call them 4x4s or 6x6s, depending on the size.

Trail slide. An earth skidding trail, reinforced on the lower side by a fender skid.

http://home.att.net/~lassen.logger/terms-t.htm

fender
a timber cluster of piles or a bag of ropes placed along a deck or bridge pier to prevent damage by anchoring ships or floating objects
fender pile pile driven on the outside edges of wharf structures to absorb the shock of ships movements and protect the pier structure

http://www.globalsecurity.org/military/library/policy/army/f...

fender - a structure that acts as a buffer to protect the portions of a bridge exposed to floating debris and water-borne traffic from collision damage; sometimes called an ice guard in regions with ice flaws

http://www.dot.state.oh.us/preventivemaintenance/Glossary/f_...