[RigglePLC]

Indoors, at 72 degrees.
In this tiny, test I compared seed sprouts when 20 seeds were sown on top of dead grass (representing thatch); this was compared with when the dead grass layer was placed on top of the seed.
For annual ryegrass the seed with the thatch on top of the seed sprouted first. This had 15 sprouts at 4 days after planting. At 5 days the tallest sprout was 2 inches tall.
Where the annual rye was seeded on top of the thatch, at 5 days, there were 5 sprouts, with a maximum height of 2 inches.
There were no sprouts from the Midnight KBG, nor from the Evolution tall fescue blend--so far.
Nothing new, nor earth-shaking so far.
Rain water was added every day, twice per day at about a half teaspoon.

I am not planning to test seed outdoors. This in spite of unusually warm temperature for February 14, 57 F, and no snow.

 

[RigglePLC]

At 6 days indoors the sprouts of annual rye sown under the grass clippings were about 3 inches tall. No germination from the bluegrass.
The Evolution fescue/rye mix had 6 sprouts in the seed under thatch (clippings) test with the tallest at 1.25 inches, (where this seed was sown on top of thatch there was 1 sprout at 1 inch.)
Outdoors, it was unusually warm this week, 57 and windy conditions. A few tiny sprouts of annual rye sown in bare soil in December, were visible at about 3/8 of an inch.
Warm temps and wind, followed by snow expected.

 

[RigglePLC]

A new test was seeded March 9th indoors at 71 degrees F. Half of the cups of soil were planted with an estimated 20 seeds on top of dead grass residue. The other half with 1/4 inch of dead grass residue on top of the seed. At nine days, the germination was about 50 percent more where the seed was covered with the residue. The perennial rye was first to emerge and attained a height (maximum) of about 3.7 inches. The tall fescue and fine fescue each attained a maximum height of the tallest sprout at about 3 inches.
The cups were watered with rain water every day.
This means it is possible to start seed on top of old grass residue. The germination may be at a lower percentage. The height of the new sprouts seeded on top of the old grass residue was only slightly less than where the seeds were covered with the dead grass residue as mulch.

 

[RigglePLC]

Creeping red fescue, tall fescue, and perennial rye seeds were planted indoors on soil in paper cups on March 9. Half of the seeds were planted under a quarter-inch residue of dead grass--and--half of the seeds were sown with no preparation on top of dead grass residue. Now after 12 days at 71 degrees F (both soil and air temp), the perennial rye had the tallest sprouts: both treatments at about 5 inches, (on the right in the photo). The "no preparation" treatment is in the near row. The seed sown under a quarter- inch of dead grass residue is the back row in the photo.
I estimated the percentage germination of the "No preparation" compared to covered seed.
Creeping red fescue (left)at 57 percent, tall fescue(center) at 37 percent and perennial rye(right) at 90 percent.