CROPTIME ONLINE VEGETABLE SCHEDULING HTTP://SMALLFARMS.OREGONSTATE.EDU/CROPTIME Nick Andrews & Heidi Noordijk OSU Small Farms Extension North Willamette Research & Extension Center nick.andrews@oregonstate.edu 503-913-9410 Collaborators Len Coop Jim Myers Ed Peachey Dan Sullivan Aaron Heinrich Heather Stoven Amy Garrett Jeremy Cowan (WSU)
René A. F. de Réaumur (1683-1757) Used daily mean temperatures to predict plant development in mid 18 th Century The importance of threshold temperatures was recognized by mid-20 th Century (i.e. Arnold, 1959) Threshold temperatures are low or high temperatures that limit development and growth
Simple average degree-days If high = 68 F & low = 45 F & Base temp for sweet corn = 50 F, then (68+45) / 2 = 56.5 56.5 50 = 6.5 degree-days
Degree-days and sine curves Cutoff methods Horizontal Intermediate Vertical No cutoff
Using degree-days David Brown, Mustard Seed Farm I have used degree days for over 20 years to schedule successive plantings of vegetables. I have made some educated guesses (but) having more information, based on some research, would be helpful in refining my schedules and maybe even using the information for more crops.
Priority crops ID d by growers Fruiting Crops (34) Snap beans (3) Tomato (5) Summer squash (5) Cucumber (4) Sweet pepper (7) Winter squash (4) Sweet corn (6) Goal > 50 crop models by Mar 2017 Root Crops (7) Carrot (3) Parsnip (4) Brassicas (15) Broccoli (4) Cabbage (6) Cauliflower (3) Kale (2) Leafy crops (7) Spinach (4) Lettuce (3)
Growth stages - Broccoli Transplant Cupping Head Initiation Mature Early Flowering
Using Croptime 1. Search for Croptime http://smallfarms.oregonstate.edu/croptime
Hit CALC/RUN Select weather station (Google maps) Select crop & variety Enter planting dates
Date Temp/Precip DD Day length Cum DD Crop events Scroll right for other planting dates
2 nd planting 3 rd planting 4 th planting Apr 1 = 88 DTM May 1 = 74 DTM Jun 1 = 68 DTM Jul 1 = 68 DTM Different seed catalogs estimate 63-94 DTM Degree-day models use local temperature data, forecasts and historical averages or forecasts to predict harvest within a few days
66-103 DTM 20-32 days difference within a season 0-14 days difference at same planting date in different seasons Average 7 days slower development in cooler years (2011-2012) than in warmer years (2013-2015)
Forecasts The dramatically different weather we have had this spring and last makes it hard to know what to expect. Tanya Murray, Sauvie Island Organics Separate grant to convert long-term weather model data to degree-days This will be an improvement over current 30-year averages Len Coop
Thermal time to maturity (2013-14 data) Transplanted broccoli 40/70F, SSHCO 50% head initiation First harvest Early flowering Accuracy (± days) Arcadia (TP) 1278 1702 1984 2.0 Green Magic (TP) 1137 1623 1828 5.0 ~3 days diff. between varieties ±15 days in catalogs Transplanted sweet pepper 52/--F, SSHCO Fruit set First green harvest First ripe harvest Accuracy (± days) Stocky Red Roaster 553 1221 1680 2.0 Gatherer s Gold 501 1237 1694 3.0 >1 day diff.
Thermal time to maturity (2013-14 data) Cucumber 50/80F, SSICO First flower First harvest Accuracy (± days) Cobra (DS) 561 870 2.88 Marketmore (TP) 358 682 4.0 Marketmore (DS) 654 952 2.5 ~11days diff. Direct seeded sweet corn 50/86, corn DD 5 true leaves 100% silk Fresh market harvest Processed market harvest Accuracy (± days) Kokanee 306 1112 1522 1635 2.6 Luscious 277 1004 1134 -- 3.75 ~16 days diff.
GDD Models for Weeds 1. Summarize the GDD requirements of selected weedy species from literature. 2.Use degree day models to predict when weeds must be removed to prevent seed production 3.Use interpretive skills of participating growers to validate and develop DD models
Background GDD Emergence Models WeedCast, Forcella May 1 planting date in western Oregon
Downy Brome seed production Dan Ball, Pendleton OSU
Hairy nightshade case study 2003 and 2004
Hairy nightshade case study Weeks of weed removal after planting Berry no/plant 250 200 150 100 50 0 2 3 0 23-Apr 7-May 21-May 4-Jun 18-Jun Snap bean planting date
Croptime Weed models What will the weed stage be at harvest? Do I need to send in a crew to hand weed before harvest to prevent weed seed rain? $300 per acre Turn in weeds after harvest
Grower estimates Do you think the seeds are viable? Grower #1 thought they were close to viable Grower #2 thought that no seeds were viable Lab results 53% viable
Weed models chosen by producers Hairy Nightshade Lambs Quarter Pigweed Crabgrass
Data collection Cotyledon stage Monitored every one to two weeks through flowering Monitored 1x per week from flowering to early seed Seed collected 2x per week from early seed to seed rain
CV (%) Pigweed model development Cotyledon to first viable seed 18 17 16 15 14 13 12 11 Pigweed First viable seed 10 40 45 50 55 60 65 Tlow (F) 2015 data Upper threshold
Hairy nightshade time to maturity Cotyledon to First Flower (DD) Cotyledon to First Flower (Days) Hairy Nightshade First Flower to First viable seed (DD) First Flower to First viable seed (Days) 778 34 1085 36
Challenges Identifying weed seedling Uncertain if degree-days will be more accurate than locally determined days
Upcoming Croptime Workshops Thur Feb 11 (10-2:30) at NWREC Sat Feb 20 OSU Small Farms Conference