Why should the percentage of allowed weed or other crop seed be under 2 percent? These other plants will compete with the desired plant for attention, rain, and desiccants
These other plants will compete with the desired plant for light, space, and nutrients
These other plants will compete with the desired plant for shelf space, threshing, and roguing
These other plants will compete with the desired plant for soil, worms, and warmth

the main thing i would use is bricks because if there is a hurricane, there is a great possibility for the house to still stand. and i would also use plexiglass windows instead of regular windows because plexiglass isn't prone to breaking.

the alkaline earth metals (beryllium (be), magnesium (mg), calcium (ca), strontium (sr), barium (ba), and radium (ra)) are a group of chemical elements in the s-block of the periodic table with very similar properties: shiny. silvery-white. hopefully this ? i didn't fully understand the question