(Salem, OR)  --  A plan to implement tighter restrictions regarding medical marijuana has the approval of an Oregon Senate special committee.  Under the measure, new regulations on the medical marijuana industry would include limiting the number of plants growers can have.  The committee, which is charged with implementing Oregon's new marijuana legalization law, has also agreed on a provision to allow local governments to ban medical marijuana dispensaries within their jurisdictions.  Measure 91, which legalizes recreational use of pot in Oregon, is set to go into effect on July 1st.