CREATE TABLE table_20913 ("Central Forest Reserve" TEXT, "Size in km\\u00b2" FLOAT, "Total plant species" FLOAT, "Tree species" FLOAT, "Endemic" FLOAT, "Threatened  ( CR , VU , EN ) " FLOAT)

How many tree species are listed when the total plant species is 258?
SELECT "Tree species" FROM table_20913 WHERE "Total plant species" = '258'
SELECT "Tree species" FROM "table_20913" WHERE "Total plant species" = '258'