error: object ref. required for non static field

Code:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Collections;


namespace RabbitGenetics
{
    
    public class JWClass
    {
        //housekeeping
        //Jersey Wooly Color Genetics


        // create list for sire data
        public List<int> siregtype = new List<int>();


        //create list for dam data
        public List<int> damgtype = new List<int>();


        // set sire & dam array size
        public const int rows = 128;
        public const int columns = 7;


        // create lists for dictionaries
        public List<int> colorslist = new List<int>();
        public List<int> gtypelist = new List<int>();


        // create sire & dam data 2D arrays
        public int[,] siredata = new int[rows, columns];
        public int[,] damdata = new int[rows, columns];


        //create offspring 1D array
        public int[] offspring = new int[14];
        
        // create sire & dam 1D arrays
        public int[] sire = new int[14];
        public int[] dam = new int[14];


        //create child 4D array
      //  public int[, , ,] child = new int[color_counter, 4];


        //Dictionaries
        public Dictionary<string, int> colors = new Dictionary<string, int> { };
        public string color; //name key
        Dictionary<string, string> geneo = new Dictionary<string, string> { };
        public string gtype; // geneotype key


        // gene groups
        public int Broken, Agouti, Brown, Colour, Dilute, Ext, Vienna;


        // Vienna types flags
        bool vienna = false; bool vm = false; bool vc = false;


        //color flags
        bool dilute = false; bool charlie = false; bool broken = false; bool rew = false;


        // data holders
        public int sen1, sen2, sa1, sa2, sb1, sb2, sc1, sc2, sd1, sd2, se1, se2, sv1, sv2;
        public int den1, den2, da1, da2, db1, db2, dc1, dc2, dd1, dd2, de1, de2, dv1, dv2;
        public char colorpct;


        //declare counters
        public int sirecounter = 0;
        public int damcounter = 0;
        public int offspringcounter = 0;
        public int totalcount = 0;
        public int color_count = 0;
        // public color_counter = 0;
        public static bool e_trap;


    } // end JWClass


    public class Genetics
    {
      // public JWClass jw;
        
        static void Main()
        {
              var  jw = new JWClass();
          //  obj = new JWClass();


            prog();
            
        } // end Main




        // start program run
          public static  void prog()
      
  {
           //array setup variiables for parsing combinations into the correct fields.
         jw.Broken = (jw.rows / 2);


            return;
        } // end prog

     } // End Class GenticsClass
} // end Namespace RabbitGenetics

I can't figure why I'm getting this error.
I want to access and/or modify vars in class JWClass from class Genetics.
I'm new to C# and OOP programming style.
My background is COBOL using the structured style

You're attempting to access the non-static instance "jw" from within a static method. Change:

Code:

public JWClass jw;

to:

Code:

public static JWClass jw;

Thanks. That did the trick.

It then showed another error where I couldn't access var rows.
Seems I can not use an instance to access it. So I used JWClass.rows and it works.

Also found out I can use an instance for all the following vars that reference the var Broken

Constants are always static, because they don't change for every instance, so it doesn't make sense to allocate memory for them for every instance.