Notes from Your Extension Agent:

Alfalfa: While scouting number of alfalfa fields across central Arizona, I found that populations of Egyptian alfalfa weevil (EAW) and aphids are variable across the area. Some fields have high populations of both pests; some one or the other higher, while some have very low populations of both EAW and aphids.
It is critical to correctly distinguish EAW larvae and adults from other insects which could be in the field at this time of year. We developed a short 1-page publication to help with that http://cals.arizona.edu/crops/cotton/files/EAW_ShortFc.pdf. Remember that varieties with rapid spring growth may be more tolerant of weevil damage, and early harvesting can mitigate damage, but surviving larvae under windrows may reduce subsequent growth.
We have four different species of aphids in alfalfa: pea aphid, blue alfalfa aphid, cowpea aphid and spotted alfalfa aphid. To help with proper ID of these four species of aphids, the Arizona Pest Management Center has a short, 1-page piece on the diagnostics for the alfalfa aphid complex http://ag.arizona.edu/crops/cotton/files/AlfalfaAphidDiagnostics.pdf. It is important to ID these species, as each of them has different economic thresholds. CLICK HERE for information about alfalfa aphids monitoring and thresholds

Small Grains: The Small Grains Advisory provides bi-weekly estimates of durum and barley growth stage for two planting dates at 12 AZMET locations from January through May.
Don’t forget to consult the most recent Small Grains Advisory HERE.
For central Arizona it looks like we are at the 5-leaf stage going into first node for early planted small grains. At this stage you will want start collecting lower stem samples for NO3-N analysis. Check out these 2 sites for information on nutrient management in small grains: https://cals.arizona.edu/crops/soils/azngrain.pdf and http://cals.arizona.edu/crops/cotton/files/Fertilizing_small_grains.pdf.
For later planted small grains you will be at the 3-leaf going to 5-leaf stage. Here you will want to scout for weeds, irrigate, and be thinking about going out in the field soon for stem collection for N analysis.

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