Here is a mowing calculator. Mowing four times per year, tractor speed can be 5-6 mph if the field(s) are not too rough. Mowing once per year will require a tractor speed of around 4-mph. Mowing every second year will limit tractor speed to 3-mph due to density of vegetation.
Mowing once per year will require 40 - 45 tractor horsepower to operate a 60" HD bush hog = 2 acres per hour.
Mowing once per year will require at least 50 tractor horsepower to operate a 72" HD bush hog = 2-1/2 acres per hour.
Mowing Calcuator:
Mowing Calcuator | How many acres can I mow in an hour
Tennessee has a lot of hills in parts, which strongly influences tractor width required for tractor stability.
Do you have hills to tractor? Are your fields on a slope?
Tractors are inherently unstable operating on sloped ground. Tractor rear wheel/tire spread, adjustable on the MX series, is a critical factor increasing compact tractor stability working sloped or uneven ground. Rear axle is the tractor component on which rear wheels/tires mount. A 6" to 10" wider rear axle substantially decreases tractor rollover potential. Tractor width is an approximation of rear axle width.
I suggest a cabbed Kubota MX5400 tractor of 4,250 pounds weight including 600 pounds for cab, 53-horsepower net, 66" width, capable of pulling a 72" heavy duty Rotary Cutter weighing 1,100 pounds through tall grass, tall weeds and brush.
Cabbed Kubota MX5400 tractor/'SSQA' Loader/4-WD/HST transmission = $42,000.
Land Pride by Kubota HD 72" Rotary Cutter/RCR2672 = $4,000.
Every tractor producer has models with above specs. This is a high sales volume category.
John Deere pricing for equivalent equipment will be the same to 5% more expensive. Other tractor brands such as very fine Kioti, LS and Branson, all three produced in Korea, are available for 5% to 15% less than Kubota. Kioti, LS and Branson share perhaps 5% of compact tractor sales and are somewhat regional in penetration. All three are growing rapidly. Be sure to select a stable dealer.
KUBOTA LINK:
*New* Kubota MX6 & MX54 Utility-Compact Tractor - YouTube
If your finances are especially sound, Kubota makes a series of deLuxe tractors in the same weights as basic MX series, the Kubota 'Grand L' models. Grand L tractors are tractor nirvana.
A $400 Bucket Spade is a very fine tractor tool for planting five to fifty trees. PHOTO