This month’s Iron Test takes place in the Kaingaroa Forest, just off the Million Dollar Highway between Murupara and Kawerau, where the Thomassen crew is operating.  The target is the robust and powerful looking John Deere 953M, coupled with a New Zealand-made Quadco QB4400 fixed felling head.

The 9 litre, 330HP, John Deere is running three hydraulic pumps, 532 litres per minute (l/min), 114 l/min and 135 l/min. It impresses with its seamless power delivery and its diversification as a bulldozer, with the Quadco proving very useful to clear excess slash to make way for the skidder, and also push in rough access tracks to assist felling and extraction with the skidders.

Operator, Jody London, chose the non-levelling base because it is what he prefers and is used to, so the bulldozer side gig makes sense from that angle too. In this pumice/ash ground, there is practically zero erosion as it is so free draining.

The large capacity Quadco QB4400 fixed felling head is obviously built to handle the toughest of felling jobs, with serious steel-work plain to see from a long way off. 
 
 With the large customised slew bearing, three heavy-duty slew motors and 255° of saw bar rotation, the QB4400 is a great choice for controlled felling applications with minimal stem breakage.
 
 To read more, get your copy of the May 2026 edition of NZ Logger magazine, on sale from 4 May. Check the link on this page to subscribe to either a printed or digital copy (or both).