You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Southern_California

Context:
Since the 1920s, motion pictures, petroleum and aircraft manufacturing have been major industries. In one of the richest agricultural regions in the U.S., cattle and citrus were major industries until farmlands were turned into suburbs. Although military spending cutbacks have had an impact, aerospace continues to be a major factor.

Question:
Outside of livestock, what else was considered a major industry in the agriculture regions?

citrus