Volume: Issue: Date: 2 1 July 1, 2010 Potato Bytes
Klamath Basin Research and Extension Center
6941 Washburn Way
Klamath Falls, Oregon 97603
(tel) 541-883-4590 (fax) 541-883-4596
http://oregonstate.edu/dept/kbrec
Brian A. Charlton, Research and Extension Agent –541-591-1255
Inside this issue:
Crop Water Use
Insect Trap Report
Soil Degree Data
Brian’s Notes
Water Use in/day
Potato Crop Water Use Average (1999‐2009)
1
2
3
4
0.30
0.20
0.10
Total P-Day Accumulation
Estimated Emergence - June 29
0.00
300.0
p‐days
Date
Potato Crop Water Use 2010
15‐May
1‐Jun
15‐Jun
100.0
0.0
0.25
Water Use in/day
200.0
04
0.20
0.15
Early
0.10
Late
0.05
0.00
6/1
6/8
6/15
6/22
6/29
Time
KBREC
Actual Water Use:
Planting Date:
Last 3 days:
Last 7 days:
Last 14 days:
Estimated Water Use:
Next 7 days:
Inches
Early
0.58
1.23
1.99
Late
0.34
0.71
N/A
1.26
0.70
05
06
07
08
09
10
Volume: Issue: Date: 2 1 July 1, 2010 Potato Bytes
Klamath Basin Research and Extension Center
6941 Washburn Way
Klamath Falls, Oregon 97603
(tel) 541-883-4590 (fax) 541-883-4596
http://oregonstate.edu/dept/kbrec
Brian A. Charlton, Research and Extension Agent –541-591-1255
Insect Trap Report
June 21 - July 1
Klamath County
TRAP
1
2
3
4
5
6
7
8
9
LOCATION
Anderson Rd
Township Rd
Transformer - Drazil Rd
Harpold - Pickett Rd
Schaupp Rd
Burgdorf - Casbeer Rd
Wu Rd
Homedale Rd - South
Springlake Rd
PTW
NA
NA
NA
NA
NA
NA
NA
NA
NA
BLH
0
0
0
0
0
0
0
0
0
OLH
10
1
2
3
1
4
2
4
2
PSY
0
0
0
0
0
0
0
0
0
NA
NA
NA
NA
NA
NA
0
0
0
0
0
0
2
0
1
1
2
1
0
0
0
0
0
0
Potato
NA
NA
NA
NA
NA
NA
NA
GPA
NA
NA
NA
NA
NA
NA
NA
PTW: Potato Tuberworm
BLH: Beet Leafhoppers
OLH: Other Leafhoppers
PSY: Psyllid
Modoc and Siskiyou
1
2
3
4
5
6
TID 5010
Frog Pond
TID 4385
TID 4260
TID 4324
TID 4232
Aphid Traps
1
2
3
4
5
6
7
Running Y
Lower Lake - West
Lower Lake - East
Malin - North West
Malin - East
South Poe Valley
Bonanza - East
Other
NA
GPA: Green Peach Aphid
NA
NA
NA
NA
NA
NA
Volume: Issue: Date: 2 1 July 1, 2010 Potato Bytes
Klamath Basin Research and Extension Center
6941 Washburn Way
Klamath Falls, Oregon 97603
(tel) 541-883-4590 (fax) 541-883-4596
http://oregonstate.edu/dept/kbrec
Brian A. Charlton, Research and Extension Agent –541-591-1255
Soil Degree-Day Accumulation -- KBREC and IREC 2010
For Root-knot nematode control, Vydate applications should begin at 800 degree-days (DD5C).
To estimate that date, add the number of Total degree-days "Total" on the day you planted
to 800. Where that value occurs in the "Total" column estimates the date on which 800 DD5C
will occur in that field. It is recommended that applications continue every 14 days until harvest.
For Stubby-root nematode control, Vydate applications should begin at 0 degree-days (at planting)
and followed by an application at the first full irrigation following emergence. An additional
application is recommended at 800 degree-days (DD5C).
Date
4/15/10
4/16/10
4/17/10
4/18/10
4/19/10
4/20/10
4/21/10
4/22/10
4/23/10
4/24/10
4/25/10
4/26/10
4/27/10
4/28/10
4/29/10
4/30/10
5/1/10
5/2/10
5/3/10
5/4/10
5/5/10
5/6/10
5/7/10
5/8/10
5/9/10
5/10/10
KBREC DD5C IREC DD5C
Daily Total Daily Total
2.8
0.0
2.8
0.0
3.6
3.6
3.5
3.5
4.0
7.6
4.1
7.6
4.7
12.3
4.8
12.4
4.8
17.1
4.8
17.2
4.2
21.4
4.5
21.6
2.4
23.7
3.1
24.7
1.8
25.5
2.7
27.4
4.1
29.7
3.9
31.3
4.3
34.0
4.6
35.9
4.5
38.4
4.6
40.6
4.3
42.8
4.7
45.3
3.6
46.3
4.2
49.5
2.6
48.9
3.5
53.0
2.1
51.0
3.1
56.1
2.0
53.0
3.4
59.5
4.2
57.2
4.4
63.9
4.5
61.7
4.7
68.7
4.8
66.5
5.4
74.1
4.1
70.6
5.2
79.3
4.5
75.1
5.2
84.6
4.0
79.1
4.7
89.3
5.0
84.2
5.1
94.3
6.0
90.2
6.4
100.7
6.1
96.3
7.0
107.7
5.5
101.8 6.6
114.3
Date
5/11/10
5/12/10
5/13/10
5/14/10
5/15/10
5/16/10
5/17/10
5/18/10
5/19/10
5/20/10
5/21/10
5/22/10
5/23/10
5/24/10
5/25/10
5/26/10
5/27/10
5/28/10
5/29/10
5/30/10
5/31/10
6/1/10
6/2/10
6/3/10
6/4/10
6/5/10
KBREC DD5C
Daily Total
4.7
106.6
5.5
112.1
7.0
119.1
7.8
126.8
8.3
135.1
8.3
143.4
10.2
153.6
7.1
160.7
7.1
167.9
6.4
174.3
6.4
180.7
5.5
186.2
5.5
191.7
5.9
197.6
5.4
203.0
5.3
208.3
5.6
213.9
6.4
220.3
7.1
227.4
7.8
235.2
8.7
243.9
12.3
256.2
11.7
267.9
10.2
278.0
12.6
290.6
12.0
302.6
IREC DD5C
Daily Total
5.4
119.7
6.1
125.8
7.7
133.5
8.9
142.4
9.7
152.1
10.2 162.3
10.6 172.9
10.3 183.2
10.2 193.4
9.2
202.6
8.5
211.0
7.3
218.4
7.0
225.4
7.4
232.8
7.2
239.9
6.9
246.8
6.9
253.7
7.3
261.0
7.7
268.7
8.6
277.3
9.7
287.0
10.3 297.3
10.4 307.7
9.7
317.5
10.0 327.4
10.5 337.9
Date
6/6/10
6/7/10
6/8/10
6/9/10
6/10/10
6/11/10
6/12/10
6/13/10
6/14/10
6/15/10
6/16/10
6/17/10
6/18/10
6/19/10
6/20/10
6/21/10
6/22/10
6/23/10
6/24/10
6/25/10
6/26/10
6/27/10
6/28/10
6/29/10
6/30/10
KBREC DD5C
Daily Total
14.0 316.6
12.6 329.2
13.8 343.0
11.5 354.5
9.7
364.2
9.8
374.0
11.2 385.2
13.2 398.4
15.2 413.6
13.3 426.9
10.4 437.3
10.3 447.6
12.1 459.7
11.0 470.6
10.7 481.3
12.6 493.9
14.6 508.5
16.6 525.1
17.6 542.7
17.0 559.7
16.8 576.4
17.8 594.2
18.8 613.0
16.6 629.6
16.0 645.6
IREC DD5C
Daily Total
11.8
349.7
12.6
362.3
13.2
375.5
13.4
388.9
12.6
401.6
11.7
413.3
12.1
425.5
13.0
438.4
14.2
452.6
14.2
466.8
12.7
479.5
12.5
492.0
13.1
505.1
13.6
518.8
13.4
532.1
13.9
546.0
15.3
561.3
16.1
577.4
17.0
594.4
17.2
611.6
17.0
628.6
17.3
645.9
18.0
663.9
18.6
682.6
17.3
699.9
Volume: Issue: Date: 2 1 July 1, 2010 Potato Bytes
Klamath Basin Research and Extension Center
6941 Washburn Way
Klamath Falls, Oregon 97603
(tel) 541-883-4590 (fax) 541-883-4596
http://oregonstate.edu/dept/kbrec
Brian A. Charlton, Research and Extension Agent –541-591-1255
Brian’s Notes
General Information: I think everyone will agree this spring has been very unique. The irrigation situation has made timely planning very difficult. As a
result, most growers have had to lease land in areas of the Basin that have not grown potatoes for a very long time, if ever. This combated with the cool
spring temperatures has presented numerous challenges combating wireworm, seed corn maggot, and quackgrass to name a few. For most, planting has
been delayed and crop emergence took slightly longer than normal. However, emerged potatoes appear to be quickly catching up with the warmer temperatures and we’re all hoping the growing season resumes some sense of normalcy through harvest. I hope you find these issues of Potato Bytes in 2010
useful and remember to contact me if you have suggestions for improvement.
Crop Water Use: Usage has definitely picked up with the warmer weather and more advanced crop growth. When feasible, look to irrigate in the evening
or at night to take advantage of reduced wind which will improve distribution uniformity and facilitate better canopy drying during the day.
Insect Trap Reports: Sticky traps were placed throughout the Klamath Basin on June 24. Basin Fertilizer & Chemical is graciously collecting them on a
weekly basis. Overall insect pressure is relatively low. Aphid numbers in yellow pan traps will be collected next week.
Flea Beetles: As most of you are aware, Tuber Flea Beetle and/or Western Potato Flea Beetle have become resident pests in the Henley area the past several years. Problem fields were noted in the Malin area last year for the first time. Potatoes that received a systemic insecticide should have ample protection during the early portion of the growing season. However, thorough scouting is needed to verify if additional foliar sprays are warranted. Treatment
thresholds are very low (1 beetle per 60 plants). Scout field edges first, if counts exceed this threshold move further into the field and repeat. Doing so
will determine if aerial applications are warranted for the entire field or can be targeted to field edges only. REMEMBER – shot hole damage on lambsquater weed is not a good indicator that an aerial application is warranted. Tuber / Western Potato Flea Beetles prefer to feed on potatoes and are rarely
observed on non-Solanaceous weeds. Damage to lambsquarter is most likely the result of Crucifer Flea Beetle which poses no risk to potatoes. Feel free
to call me for a field visit if needed.
Soil Degree-Day Accumulation: Initial values recorded at OSU-KBREC were much cooler than previous years as the crop canopy around the AgriMet
was not mowed and irrigated this spring. After thoroughly analyzing GDD values for the past 5 years and closely correlating these to values at UC-IREC I
made some slight adjustments. I’m relatively confident the values presented to date are very close to what we would have actually expected. Values are
about a week behind last year. The 800 DD target is still a ways off for early planted potatoes but could come quickly if temperatures really heat up.
Please read the recommendations on the top of page 2 if you plan on using Vydate for nematode control/suppression.
P-day Accumulation: P-days are a measure of potato physiological growth from the time of emergence. Depending on emergence dates, growth this year
is considerably behind last year but very similar to 2005 and 2008. Central Oregon research and extension specialists have noted a strong correlation with
300 pdays and the onset of Early Blight. Early emerged potatoes have not quite reached this target but should in the next 7-10 days. A preventative fungicide might be warranted if you routinely experience problems with this disease as the target is getting close.
Other: The Columbia Basin has recently confirmed the presence of late blight in at least 4 fields as of 6/30. Two of these fields had been on a 10-14 application schedule of fungicides which clearly did not provide adequate protection against infection. Potato Specialists have been recommending a 7 day
schedule using manzate and chlorothalonil products. We’ve been fortunate this disease has not been a real problem in the Klamath Basin; however, several
fields in the late ‘90s saw the devastating results of this pathogen. As such, this disease is always a threat and preventative methods continue to be necessary to disrupt the disease triangle. Be cognizant of your irrigation schedule to prevent periods of excessive moisture in the lower canopy. Night irrigations not only take advantage of reduced wind which improves distribution uniformity but allows for better canopy drying during the day. Continue to
aggressively scout fields in wet areas for infection and bring suspect samples for confirmation and take of any cull piles!
Potato Bytes published by: Brian A. Charlton, Research and Extension Agent 541-591-1255
Darrin Culp, Fac. Res. Asst 541-891-0784