Steven, I can't see if you have a bucket on your tractor, but you can cover up a 24" trench just as easily as as a 10" trench with your bucket! I also see a reddish color in your soil and trenching buckets are notorious for packing solid when used in clay... you get a bucket full, swing, dump and nothing comes out! After 20 minutes of a hammer and bar of some sort, your bucket is empty and ready for it's next load, only to repeat! Bob
Mudds Custom in Iowa makes a great bucket for a fair price but I agree with rwmeyer about clay. I have a 9" trenching bucket that I have used on several projects but when the clay is wet it is tough to empty it at times. I would ask myself if it is really necessary. If it is a one off project maybe renting a mini excavator would be best. Way faster than a backhoe, unless you do like I do, have the wife run the tractor while I operate the hoe. This is true quality time in my book.