Why was A Discourse and View of Virginia written?

William Berkeley's 1663 treatise, A Discourse and View of Virginia, had four purposes. First, it sought to encourage Virginia farmers to diversify their economy by increasing the production of what Berkeley labels "commodities," including "Silk, Flax, Hemp, Pitch, Pot-ashes and Iron." Second, he condemned the ubiquitous growing of tobacco. Berkeley argued tobacco had become monolithic, impacting every aspect of colonial life. It was used as a cash crop, a mode of currency, and a method for applying credit and debit. Berkeley used a barrage of complaints against the crop, calling it a "vicious weed."
Third, Berkeley hoped that through economic diversification and less emphasis on tobacco, the colonies would be able to export their goods not only to the English, but also to the rest of the world. He goes on to say that because Virginia farmers deal only in tobacco they are at the mercy of English merchants who can "give us what they please for it." Finally, Berkeley asked the king to increase the tariff on tobacco and give part of the money back to the colony "to resist the Indians."
Although Berkeley was twice governor of the Virginia Colony and had the full support of the English crown for his program of diversification, he ultimately failed and was challenged by other colonists during Bacon's Rebellion. Moreover, the English government denied Berkeley's proposal to return tax money to the colonists. This habit by the English king would eventually lead to the American Revolution.
http://nationalhumanitiescenter.org/pds/amerbegin/permanence/text5/BerkeleyVirginia.pdf