Currently there are some fields that are entering GS 6 in wheat today in fact it is possible we had some wheat going into this phase prior to freeze out in December. You will note some key principles in identifying the stages. If you feel the stem at the base and slide your finger up the stem you will note a joint that is enlarged this is the first inter node. Once this is formed the GS stage 6 is formed. There are some key things to be looking for at this stage. The low hanging fruit is controlling weeds. For most products you have until GS 7 to make this application. Not sure what weeds you have in the field? I find the Early Spring weeds of No till the best reference for this time of year. Here is a copy. Early Spring Weeds of No Till If the wheat is this far along one might be considering additional nitrogen for it is at this stage that peak uptake of N occurs during this GS 6 and GS9 stage(source AG DWEEB)
as this field condition might lead to further infection and a fungicide may be warranted at this stage PARTICULARLY on varieties that are not tolerant of the disease. If you decide to apply a fungicide utilize the included reference to determine the most economical product and ensure it has activity on both Septoria and Powdery Mildew. Dry weather can halt powdery mildew growth and typically wet weather brings on the Septoria disease so consider the forecast as well. The addition of Palisade EC (it does have a WARNING label so protect your eyes and wear proper safety equipment) a recent growth regulator might be beneficial as well to prevent excessive growth and the ideal timing for this application once in GS 6 is in play. Here is the label discussion on timing. Single application: Apply Palisade EC from Feekes growth stage 4 (pseudostem erection) through Feekes growth stage 7 (node formation). Apply before Feekes 8 (when the last leaf is visible). Split application: Make the first application at Feekes 4-5 and a second application at Feekes 7. Apply no more than 14.4 fl oz/A total. Split application in barley: Make the fi rst application at Feekes 4-6 and a second application at Feekes 7-8. Use the higher rate when 1) varieties are prone to lodging, or 2) the crop is intensively managed.
So there is alot to consider once the plant enters this growth period. We have numerous references to assist in any of these decisions in the Agronomy Guide.
Finally, Wisconsin Extension has this handy guide similar to our Penn State Guide but in color and includes a little timing detail for key pests.