//---------------------------------------------------------------------

        private void MakeAndCheckCohorts(int timestep)
        {
            //  All cohort ages are multiples of 10, and this code requires
            //  that the given timestep divides 10 evenly (to mimic binning
            //  process of the initial communities).
            Assert.IsTrue(10 % timestep == 0);

            isTimestep1 = (timestep == 1);
            Landis.Biomass.Cohorts.Initialize(timestep, mockCalculator);
            InitialBiomass.Initialize(timestep);
            SiteCohorts cohorts = InitialBiomass.MakeBiomassCohorts(ageCohorts,
                                                                    activeSite,
                                                                    ComputeInitialBiomass);

            CheckCohorts(cohorts[abiebals], abiebalsAges);
            CheckCohorts(cohorts[betualle], betualleAges);
        }
        //---------------------------------------------------------------------

        private void InitializeAgeCohorts()
        {
            abiebalsAges = new List <ushort>(new ushort[] { 30, 40, 50, 150, 170 });
            betualleAges = new List <ushort>(new ushort[] { 100, 120, 280, 290 });

            //  Work with ages from oldest to youngest
            abiebalsAges.Sort(Landis.AgeCohort.Util.WhichIsOlder);
            betualleAges.Sort(Landis.AgeCohort.Util.WhichIsOlder);

            List <AgeCohort.ISpeciesCohorts> speciesCohortList = new List <AgeCohort.ISpeciesCohorts>();

            speciesCohortList.Add(new AgeCohort.SpeciesCohorts(abiebals,
                                                               abiebalsAges));
            speciesCohortList.Add(new AgeCohort.SpeciesCohorts(betualle,
                                                               betualleAges));
            AgeCohort.SiteCohorts siteCohorts = new AgeCohort.SiteCohorts(speciesCohortList);

            ageCohorts = InitialBiomass.SortCohorts(siteCohorts);
        }