This week the plants are at approximately the 2 and 3 leaf stage.   Merit has just started to develop its 1st tiller along with its coleoptilar tiller.   Whitebird is still developing its 3rd leaf.  The alternate leaf pattern is becoming more visible for both wheat and barley plants.  Leaves form alternately on cereals with odd numbered leaves arising from one side of the stem and even numbered leaves arising from the opposite side of the stem.  When counting leaves on cereals, the first formed leaf is numbered 1, the second leaf is numbered 2, and so on.   Tillers are counted in the same manner.  Tiller 1 arises from the base of leaf 1, tiller 2 arises from the base of tiller 2, etc.

Growing degree days for week of 4/26 - 5/2 = 110 
Accumulated growing degree days (emergence to 5/2) = 277.5

Merit 2-row Barley

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Merit: 2-row spring barley.  Picture taken 5/3/99 at the 3 leaf stage.   Zadoks scale: 13, Feekes scale: 1, Haun scale: 3.2.

Note: Merit is starting to develop its 1st tiller (Tiller 1) along with the coleoptilar tiller (also known as the T0 tiller).  Tiller 1 arises from the base of leaf 1 and emerges near the leaf collar of leaf 1.  Normally, tiller 1 starts to emerge when the plant has between 3 and 4 leaves.  The T0 tiller arises from the seed and is often used as an indicator of seed and/or seedbed quality.  When it forms, the T0 tiller normally becomes visible when the plant has approx. 3-4 main stem leaves.  On plants with T0 tillers, this tiller usually contributes more yield than any other tiller.  The T0 tiller is quite sensitive to environmental conditions and does not generally appear if there is significant seedbed stress. 

Seedlots with high vigor will have more seedlings that develop T0 tillers than will seed lots of lower vigor.  When comparing seedlots growing in similar seedbed conditions, the percent of plants with T0 tillers can be used as one measure of seed vigor.  When comparing the same seedlot in different seedbed conditions, the percent of plants with T0 tillers can be used as a measure of seedbed stress.  Seeding deeper than is needed also reduces the number of T0 tillers that form. 

Whitebird Soft White Spring Wheat

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Whitebird: soft white spring wheat..  Picture taken 5/3/99 at the 2 leaf stage.  Zadoks scale: 13, Feekes scale: 1, Haun scale: 2.5.

Growers should begin scouting fields for wild oats at this time.  Wild oats develop in a similar manner as wheat and barley.  Speed of leaf development is also similar.  Because wild oat susceptibility to post-emergence herbicides is influenced by development stage, it is important to properly identify the stages.  One can also use the GDD information to estimate how long it will take wheat, barley, or wild oat to reach specific stages.  Many wild oat herbicides use seedling growth stages in label recommendations.

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