a lowered tube position used for transport is shown in phantom the frame 14 is supported by two front castor wheels 15 and 16 and a single rear wheel 17 the two castor wheels are mounted upon a front axle 13 or transverse frame member and are separated by a fairly large tread width for stability and are placed ahead of the tractor this configuration requires that the auger tube has adequate reach beyond the front castor wheels but provides the stability necessary for very long auger units the frame 14 includes a longitudinally extending member 14a extending rearwardly from the axle or transverse frame member 13 and a diagonal member 14b which converges rearwardly from adjacent the outer end of axle 13 to a relatively short transverse member 14c the undercarriage 10 is attached to the tractor through a rear hinged hitch frame member 18 and a front side brace member 19 these two hitch members cause the undercarriage to maintain a constant position relative to the tractor the rear hitch frame member 18 is pivotally secured to tractor draw bar 18a by means of pin 18b and pivots about a longitudinal axis 21 at the back of the undercarriage frame 14 see fig2 it is provided with a hitch lug 22 at the distal end extending at right angles therefrom which also pivots.