Research and IPM

Phenology Model Database

Yellow Nutsedge

Scientific name: Cyperus esculentus

Phenology models predict timing of events in an organism's development. For many organisms which cannot internally regulate their own temperature, development is dependent on temperatures to which they are exposed in the environment.

Note: Before using a model that was not field tested in your location, you should test the model for one or more seasons under your conditions to verify that it will work for you.

Model 1 of 3

Wilen, C.A., J.S. Holt and W.B. McCloskey. 1996. Predicting yellow nutsedge (Cyperus esculentus) emergence using degree-day models. Weed Science. 44: 821-829.

See also: Wilen, C.A., J.S. Holt and W.B. McCloskey. 1996. Effects of soil moisture on observed and predicted yellow nutsedge (Cyperus esculentus L.) emergence. Weed Science. 44: 890-896.

Location of study: Southern California (field studies) Note: This model is for well-watered conditions.

Developmental thresholds

Lower:	53.0°F	(11.67°C)
Upper:	78.0°F	(25.56°C)

Method of calculation:	Single Sine
Cutoff method:	Intermediate

Degree-day accumulations required for each stage of development

Biofix: Date of lowest air temperature or planting date, whichever is later

Cultivation can be timed to remove the first flush of tubers to allow for approximately 2 weeks of reduction of yellow nutsedge competition.

Model 2 of 3

Wilen, C.A., J.S. Holt and W.B. McCloskey.1996. Predicting yellow nutsedge (Cyperus esculentus) emergence using degree-day models. Weed Science. 44: 821-829.

See also: Wilen, C.A., J.S. Holt and W.B. McCloskey. 1996. Effects of soil moisture on observed and predicted yellow nutsedge (Cyperus esculentus L.) emergence. Weed Science: 44 890-896.

Location of study: Southern California (field studies) Note: This model is for well-watered conditions.

Developmental thresholds

Lower:	52F	(11.11°C)
Upper:	86F	(30.00°C)

Method of calculation:	Single Sine
Cutoff method:	Vertical

Degree-day accumulations required for each stage of development

Biofix: Date of lowest air temperature or planting date, whicher is later

Cultivation can be timed to remove the first flush of tubers to allow for approximately 2 weeks of reduction of yellow nutsedge competition.

Model 3 of 3

Wilen, C.A., J.S. Holt and W.B. McCloskey. 1996. Predicting yellow nutsedge (Cyperus esculentus) emergence using degree-day models. Weed Science. 44: 821-829.

See also: Wilen, C.A., J.S. Holt and W.B. McCloskey. 1996. Effects of soil moisture on observed and predicted yellow nutsedge (Cyperus esculentus) emergence. Weed Science. 44: 890-896.

Location of study: Southern Arizona (field studies) Note: This model works for well-watered conditions.

Developmental thresholds

Method of calculation:	Double Sine
Cutoff method:	Intermediate

Degree-day accumulations required for each stage of development

Biofix: Date of lowest air temperature or planting date, whichever is later

Pre-plant cultivation can be timed to remove the first flush of tubers to allow for approximately 2 weeks of reduction of yellow nutsedge competition.

This Arizona model needs further validation to be useful for weed management.