Season shown in 3 of Ohio's 88 counties. Explore Ohio
No result yet (12)
Recorded, too few records for a result (58)
Recorded, season not shown (15)
Season shown (3)
Boundaries: U.S. Census Bureau, 2025 Cartographic Boundary Files, 1:500,000. Show as a table
Counties as a table
hemp dogbane by Ohio county: records and mapped range
County
Records
Adams County
22 · Recorded, season not shown
Allen County
Recorded, too few records for a result
Ashland County
Recorded, too few records for a result
Ashtabula County
Recorded, too few records for a result
Athens County
32 · Recorded, season not shown
Auglaize County
No qualifying records yet
Belmont County
Recorded, too few records for a result
Brown County
Recorded, too few records for a result
Butler County
27 · Recorded, season not shown
Carroll County
Recorded, too few records for a result
Champaign County
Recorded, too few records for a result
Clark County
Recorded, too few records for a result
Clermont County
59 · Season shown
Clinton County
Recorded, too few records for a result
Columbiana County
Recorded, too few records for a result
Coshocton County
No qualifying records yet
Crawford County
Recorded, too few records for a result
Cuyahoga County
149 · Recorded, season not shown
Darke County
Recorded, too few records for a result
Defiance County
Recorded, too few records for a result
Delaware County
31 · Recorded, season not shown
Erie County
Recorded, too few records for a result
Fairfield County
Recorded, too few records for a result
Fayette County
Recorded, too few records for a result
Franklin County
124 · Recorded, season not shown
Fulton County
No qualifying records yet
Gallia County
Recorded, too few records for a result
Geauga County
21 · Recorded, season not shown
Greene County
20 · Recorded, season not shown
Guernsey County
Recorded, too few records for a result
Hamilton County
150 · Recorded, season not shown
Hancock County
Recorded, too few records for a result
Hardin County
Recorded, too few records for a result
Harrison County
Recorded, too few records for a result
Henry County
Recorded, too few records for a result
Highland County
No qualifying records yet
Hocking County
Recorded, too few records for a result
Holmes County
Recorded, too few records for a result
Huron County
Recorded, too few records for a result
Jackson County
Recorded, too few records for a result
Jefferson County
Recorded, too few records for a result
Knox County
Recorded, too few records for a result
Lake County
29 · Season shown
Lawrence County
Recorded, too few records for a result
Licking County
Recorded, too few records for a result
Logan County
No qualifying records yet
Lorain County
45 · Recorded, season not shown
Lucas County
30 · Season shown
Madison County
Recorded, too few records for a result
Mahoning County
Recorded, too few records for a result
Marion County
Recorded, too few records for a result
Medina County
26 · Recorded, season not shown
Meigs County
Recorded, too few records for a result
Mercer County
No qualifying records yet
Miami County
Recorded, too few records for a result
Monroe County
Recorded, too few records for a result
Montgomery County
Recorded, too few records for a result
Morgan County
Recorded, too few records for a result
Morrow County
Recorded, too few records for a result
Muskingum County
Recorded, too few records for a result
Noble County
Recorded, too few records for a result
Ottawa County
Recorded, too few records for a result
Paulding County
No qualifying records yet
Perry County
No qualifying records yet
Pickaway County
Recorded, too few records for a result
Pike County
Recorded, too few records for a result
Portage County
25 · Recorded, season not shown
Preble County
Recorded, too few records for a result
Putnam County
No qualifying records yet
Richland County
Recorded, too few records for a result
Ross County
Recorded, too few records for a result
Sandusky County
Recorded, too few records for a result
Scioto County
Recorded, too few records for a result
Seneca County
Recorded, too few records for a result
Shelby County
No qualifying records yet
Stark County
Recorded, too few records for a result
Summit County
98 · Recorded, season not shown
Trumbull County
Recorded, too few records for a result
Tuscarawas County
Recorded, too few records for a result
Union County
Recorded, too few records for a result
Van Wert County
No qualifying records yet
Vinton County
Recorded, too few records for a result
Warren County
37 · Recorded, season not shown
Washington County
Recorded, too few records for a result
Wayne County
22 · Recorded, season not shown
Williams County
No qualifying records yet
Wood County
Recorded, too few records for a result
Wyandot County
Recorded, too few records for a result
No mapped range from the range source used, the USGS Gap Analysis Project, which maps land vertebrates only.
Season
When it is recorded
In Portage County
Not enough evidence
The weeks are still too uncertain to show a season. Based on 25 records in 8 of the 10 years from 2016 to 2025, above the minimum of 20 records from 5 different years.
JanFebMarAprMayJunJulAugSepOctNovDec
Show over the bars
Recording in Portage County · records of all species each week, 31,804 in all
Records per week from 25 records in 8 of the 10 years from 2016 to 2025. Shows when people recorded it, not a season or how common it is.
Show as a table
Records of hemp dogbane in Portage County each week, and records of all species
Week
Records of hemp dogbane
Years recorded
Records of all species
Jan 4–10
0
0
44
Jan 11–17
0
0
56
Jan 18–24
0
0
31
Jan 25–31
0
0
67
Feb 1–7
0
0
66
Feb 8–14
0
0
74
Feb 15–21
2
2
72
Feb 22–28
0
0
80
Mar 1–7
0
0
109
Mar 8–14
0
0
146
Mar 15–21
0
0
152
Mar 22–28
0
0
140
Mar 29 – Apr 4
0
0
277
Apr 5–11
0
0
451
Apr 12–18
1
1
648
Apr 19–25
0
0
641
Apr 26 – May 2
1
1
849
May 3–9
0
0
1,174
May 10–16
0
0
788
May 17–23
0
0
1,091
May 24–30
0
0
753
May 31 – Jun 6
2
2
782
Jun 7–13
1
1
1,242
Jun 14–20
1
1
1,568
Jun 21–27
2
2
1,383
Jun 28 – Jul 4
0
0
1,344
Jul 5–11
3
3
1,357
Jul 12–18
1
1
1,310
Jul 19–25
1
1
1,431
Jul 26 – Aug 1
2
1
1,439
Aug 2–8
2
2
1,037
Aug 9–15
2
2
1,056
Aug 16–22
0
0
1,145
Aug 23–29
0
0
911
Aug 30 – Sep 5
1
1
930
Sep 6–12
1
1
986
Sep 13–19
0
0
974
Sep 20–26
0
0
1,199
Sep 27 – Oct 3
1
1
985
Oct 4–10
1
1
516
Oct 11–17
0
0
417
Oct 18–24
0
0
435
Oct 25–31
0
0
401
Nov 1–7
0
0
278
Nov 8–14
0
0
251
Nov 15–21
0
0
228
Nov 22–28
0
0
130
Nov 29 – Dec 5
0
0
82
Dec 6–12
0
0
79
Dec 13–19
0
0
69
Dec 20–26
0
0
53
Dec 27 – Jan 2
0
0
77
Reported in flower
No records here show flowers yet, so there is no flowering season to show. One needs at least 20 records from 5 different years.
Reported in fruit
No records here show fruit yet, so there is no fruiting season to show. One needs at least 20 records from 5 different years.
In Ohio
Late April to late September, middle week Jul 5–11
Middle week · Jul 5–11
This week · Nov 8–14
JanFebMarAprMayJunJulAugSepOctNovDec
Show over the bars
Recording in Ohio · records of all species each week, 1,691,199 in all
Records per week from 1,684 records in 10 of the 10 years from 2016 to 2025. Shows when people recorded it, not how common it is. The grey bars show how many records of all species were made here each week, so you can see when recording itself was high or low; the season is not adjusted by them.
Recorded on 895 dates. Latest record: December 2025.
Show as a table
Records of hemp dogbane in Ohio each week, and records of all species
Week
Records of hemp dogbane
Years recorded
Records of all species
Jan 4–10
1
1
6,211
Jan 11–17
2
2
5,146
Jan 18–24
2
2
4,645
Jan 25–31
2
2
4,698
Feb 1–7
6
5
6,023
Feb 8–14
3
2
5,888
Feb 15–21
4
3
5,436
Feb 22–28
8
5
6,846
Mar 1–7
4
4
8,321
Mar 8–14
6
4
10,384
Mar 15–21
4
3
12,620
Mar 22–28
3
2
13,949
Mar 29 – Apr 4
6
4
19,661
Apr 5–11
4
2
26,860
Apr 12–18
5
4
39,925
Apr 19–25
8
6
41,623
Apr 26 – May 2
20
7
56,391
May 3–9
15
6
52,952
May 10–16
14
6
53,785
May 17–23
54
9
57,698
May 24–30
55
10
54,651
May 31 – Jun 6
90
8
53,099
Jun 7–13
102
10
53,700
Jun 14–20
140
9
56,625
Jun 21–27
135
9
55,361
Jun 28 – Jul 4
141
9
58,477
Jul 5–11
94
10
61,336
Jul 12–18
100
10
64,722
Jul 19–25
67
10
69,753
Jul 26 – Aug 1
73
10
59,416
Aug 2–8
72
9
59,712
Aug 9–15
63
9
55,994
Aug 16–22
56
9
54,328
Aug 23–29
38
10
51,772
Aug 30 – Sep 5
42
8
57,167
Sep 6–12
50
8
59,075
Sep 13–19
35
8
54,543
Sep 20–26
34
8
45,860
Sep 27 – Oct 3
42
9
43,180
Oct 4–10
23
8
37,841
Oct 11–17
14
6
30,824
Oct 18–24
15
6
21,156
Oct 25–31
4
2
19,021
Nov 1–7
4
3
14,172
Nov 8–14
7
5
12,621
Nov 15–21
0
0
7,965
Nov 22–28
5
3
8,136
Nov 29 – Dec 5
1
1
6,083
Dec 6–12
1
1
6,004
Dec 13–19
7
4
5,423
Dec 20–26
0
0
5,661
Dec 27 – Jan 2
3
2
8,459
Reported in flower
Usually reported in flower early June to early August, middle week Jun 28 – Jul 4.
From 67 records that show flowers. Not every photo of a plant in flower is marked as flowering, so this shows when people reported it in flower, not when it flowers.
Reported in fruit
Usually reported in fruit early August to late April, middle week Oct 11–17.
From 75 records that show fruit. Not every photo of a plant in fruit is marked as fruiting, so this shows when people reported it in fruit, not when it fruits.
What these results show
These results show when people recorded a species, not when or where it occurs. Missing weeks and low counts do not mean absence or scarcity, and counts are not abundance. Contributed records reflect where, when and what people chose to observe.
Identification
How to identify it
Telling it apart
From what Ohio’s records show. Only what the records support is shown.
common milkweedAsclepias syriacaOften confused in Ohio: 94 identifications in Ohio named one where the other was meant
spreading dogbaneApocynum androsaemifolium318 identifications worldwide named one where the other was meant
prairie milkweedAsclepias sullivantii94 identifications worldwide named one where the other was meant
swamp milkweedAsclepias incarnata76 identifications worldwide named one where the other was meant
poke milkweedAsclepias exaltata17 identifications worldwide named one where the other was meant
From iNaturalist’s similar-species counts, refreshed monthly: confusions in Ohio first, then worldwide. Only species with an Ohio result are listed.
Land cover where it is recorded
Land cover
Its recordsAll Ohio records
Developed
47%49%
Farmland
26%11%
Forest
19%31%
Wetland
4%5%
Open water
2%3%
Grassland and shrub
1%0.9%
Barren
0.8%0.6%
From 1,018 records placed within 100 m, beside all Ohio records placed the same way. People record where they go, so this shows where records come from, not where the species lives. Land cover: USGS Annual NLCD, 2025 (opens in a new tab)
Sources
Where these results come from
Records from iNaturalist research-grade observations and expert-identified GBIF datasets, CC0, CC BY and CC BY-NC. Sources
Seasons use the published method and its evidence thresholds. Methods
A spreadsheet (CSV) with a link to each record, on iNaturalist or GBIF. Records whose location was hidden by the observer or the source are counted but not linked.
