title: How can I group specific 'months' from a vector and classify them as a chosen season in R?
body: <p>So I'm new to R as I have to use it for a research project on chickens. My facilitator has said to look to see if the months/seasons cause any confounding in our data, but hasn't said how other than showed us how to take our column of dates and make it into a vector of months:</p>
  
  <p><img src="https://i.stack.imgur.com/ac33E.png" alt="enter image description here"></p>
  
  <p>How can I take out specific months from the month_placed vector (e.g. 01,10,11,12) and classify them as a season e.g. winter?</p>
  
  <p>Many thanks for any suggestions or simpler ways to do it!</p>