The white clover has cyanide which is in fact poisonous but the plain clover does not have this genetic trait
There are two types of clovers which are the regular green ones or the white stripped clover
In Minnesota the monthly temperature gets as cold as -2.9 degrees which the population of plain clovers is more common
In North Carolina, it gets as hot as 88.3 degrees which the stripped clover population is more common
As for the plain clovers they don't need much sun which is why theyre more common in colder areas and if in hotter areas they would die out a lot faster
So the reason why the white stripped clover is more common in the hotter areas is because since it has cyanide it takes a lot more energy to produce and photosynthesis produces energy so the sun is needed for the process. Which is needed for survival
The rain is also different in Minnesota and North Carolina. Minnesota gets less rain while North Carolina gets more rain. And again the stripped clovers need rain as well for photosynthesis while the plain ones don't need much. And herbivores don't show up as much in Minnesota
Now the reason why the white stripped clover is able to survive and reproduce more is because its poisonous. Snails mainly eat clovers and because they know what is dangerous to eat they mainly eat the plain clovers so they won't die
So since snails know what's good and bad for them they don't eat the stripped clovers which leaves more population of the stripped leaves to reproduce