Field [in-には] wild [gen-の] flower [subj-が] many exist.
Demonstrates the use of たくさんある for 'there are many,' alongside the inanimate existence verb ある. Note that 花 being inanimate takes ある, not いる. 野生 ('wild') as a noun forms possessive-like compounds with の — 野生の動物, 野生の花.