Gayophytum diffusum

{{Short description|Plant species in the evening primrose family}}

{{Speciesbox

| status = {{TNCStatus}}

| status_system = TNC

| status_ref = {{Cite NatureServe |date=2 May 2025 |id=2.131439 |title=Gayophytum diffusum |access-date=30 May 2025}}

| genus = Gayophytum

| species = diffusum

| authority = Torr. & A.Gray

| subdivision_ranks = Subspecies

| subdivision_ref = {{cite POWO |id=317588-2 |title=Gayophytum diffusum Torr. & A.Gray |access-date=30 May 2025}}

| subdivision = {{Species list |abbreviated=yes

| Gayophytum diffusum subsp. diffusum |

| Gayophytum diffusum subsp. parviflorum |

}}

| synonyms_ref = {{cite POWO |id=77230743-1 |title=Gayophytum diffusum subsp. diffusum |access-date=30 May 2025}}{{cite POWO |id=107962-2 |title=Gayophytum diffusum subsp. parviflorum F.H.Lewis & Szweyk. |access-date=30 May 2025}}

| synonyms = {{Collapsible list | {{Species list

| Gayophytum diffusum var. typicum | Munz

| Gayophytum intermedium | Rydb.

| Gayophytum lasiospermum | Greene

| Oenothera albescens | S.Watson

| Oenothera diffusa | Nutt.

| Oenothera gayophytum f. diffusa | (Torr. & A.Gray) H.Lév.

| Oenothera purpurea | Benth.

}}

}}

}}

Gayophytum diffusum is a species of flowering plant in the evening primrose family known by the common name spreading groundsmoke. It is native to western North America where it is a common member of many different habitats. This is a spindly, branching annual herb reaching a maximum height of about half a meter. Its thin stems have sparse narrow leaves a few centimeters long. The occasional flowers are petite and usually white in color. The fruit is a cylindrical, knobby capsule up to 1.5 centimeters long.