CREATE TABLE table_203_700 (id DECIMAL, "year" DECIMAL, "species" TEXT, "height" TEXT, "location grown" TEXT, "state" TEXT, "notes" TEXT)

what species of tree was the tallest one used ?
SELECT "species" FROM table_203_700 ORDER BY "height" DESC LIMIT 1
SELECT "species" FROM "table_203_700" ORDER BY "height" DESC NULLS LAST LIMIT 1