No more Thermal Bluegrass from commercial suppliers

[DA Quality Lawn & YS]

Would disagree with the use of TTTF in northern climates. Some of the best seeding I have done was a TTTF/KBG/Per Rye mix.

[Skipster]

Originally Posted by ProStreetCamaro

Very nice explanation. I have read that this hybrid took on traditional physical bluegrass characteristics yet has the heat tolerance of texas bluegrass and has been tested in the deep south with good results. In my area if these findings are true Thermal Blue could be a game changer around here. Everything here is TTTF and I have never seen a lawn that did not have bare are weak spots by late summer.

I feel with a good stand of Thermal Blue mixed in with the TTTF these bare and weak areas will still occur but will naturally fill back in come fall. Also with a healthy stand of Thermal it may help minimize turf tearing due to the dense shallow root system of bluegrass.

My explanation was the quick and dirty version -- it's really a bit more involved than that. Texas bluegrass (TBG) is an out-crossing dioecious plant that usually has poor quality, poor stand density, coarse texture, pale color, and poor seed production. But, it's better in the heat and drought than Kentucky bluegrass (KBG). So, female TBG plants were crossed with KBG plants, then the daughter plants were crossed again with another KBG selection (called back-crossing), and those daughter plants were crossed one more time with a different KBG selection.

So, for about half of the available hybrid bluegrasses (there are about 10 that I can think of), they were back-crossed to KBG twice. Some were back-crossed 3 to 5 times. The point was to get something resembling KBG that was more heat and dought tolerant than KBG. If you've ever seen TBG by itself, you would never want it in a lawn. If someone put TBG in fron of you and told you that they were going ot use it to make lawn grasses with, you would laugh in their face and tell them they're stupid. That's why all the back-crossed were needed.

I don't think these hybrids have lived up to their hype. In several university trials, they were no different from tall fescue in their water requirements or disease issues and they took much longer to establish than tall fescue (which is why Scotts puts so much tall fescue in their blend). No one would want to want 3 or 4 months for a lawn to fill in when the tall fescue will do it in a couple of weeks.

[Smallaxe]

That made sense... thanks for the info...

[maynardGkeynes]

The thing with the heat tolerant bluegrasses is that they are heat tolerant, not drought tolerant, a distinction that seems to get lost in both the university studies and the NTEP analysis. I have used Thermal Blue, Solar Green, and Thermal Blue Blaze. TB establishes quickly, and does well in the shade. The color is on the lighter side, however. SG is simply too light green to blend with most elite types. TBB is quite dark in color, but it is little slow to establish. Dura Blue, which I have not used, is said to have a very dark color, but is extremely slow to establish. An ideal blend would be 50/50 TB/TBB. With irrigation, they will do quite well, and stay green a little longer than KBG. I prefer them to TTTF, which does not like temps above 90, and is pretty prone to brown patch in compacted (moist) soils.