What I found shocked me! The data show that soil temperatures reached 52 degrees F. on Feb. 24 in 2000, Feb. 25 in 2001, Mar. 14 in 2002 and Mar. 4 in 2003. My timing advice has been wrong ! To get good crabgrass control in Atlanta you should apply the pre-emergent on March 1, not March 15.Otherwise the seed will sprout beforehandâ¦.and most pre-emergent chemicals do not control crabgrass seedlings.hat I found shocked me! The data show that soil temperatures reached 52 degrees F. on Feb. 24 in 2000, Feb. 25 in 2001, Mar. 14 in 2002 and Mar. 4 in 2003. My timing advice has been wrong ! To get good crabgrass control in Atlanta you should apply the pre-emergent on March 1, not March 15.
  0.4 of an inch Answer   There are 2.54 centimeters in 1 inch, so 1 centimeter is 0.394 inches.
Is 1 inch exactly 2.54 cm? I mean how precise is this conversion? Is 1 inch = 2.540000 cm? If this conversion is only precise up to one hundredth of a centimeter, thEn that leaves half a hundredth of a centimeter of uncertainty, or approximately 2 mil of uncertainty, which can be significant in machining.