We removed three semi-mature African tulip trees and about five umbrella trees from the bottom of one of our paddocks. All we did was chop them off at the base and pile the top half of these trees in a big pile (will chip later). We will then monitor these stumps for re-growth and if required undertake some additional treatment (maybe salt).
Here are some piccies of these two offending weeds.
African Tulip Tree
In addition, to chain-sawing the trees out, I choose to remove a small patch (about 5m x 1.5m) of broad-leaf paspalum. This is a shade-tolerant, non-native, hardy grass species, which out-competes many of our native grasses. I employed the assistance of a fork and just loosened the soil around the base of each individual outcrop and removed them to the domestic waste bin once out of the ground. I did this action about three weeks ago and so far no new outcrops of this grass have sprung up in the area of 'treatment'.
Hope these treatment options hold and with my revegetation money I will look to establish a bit of a native cover crop/midstorey to replace these weed species and provide some additional protection for my overstorey eucalypts.